diff --git a/interface/resources/qml/Stats.qml b/interface/resources/qml/Stats.qml
index d5cfcff1e2..26682d3db8 100644
--- a/interface/resources/qml/Stats.qml
+++ b/interface/resources/qml/Stats.qml
@@ -193,18 +193,63 @@ Item {
                         text: "Yaw: " + root.yaw.toFixed(1)
                     }
                     StatText {
-                        visible: root.animStackNames.length > 0;
-                        text: "Anim Stack Names:"
+                        visible: root.animAlphaValues.length > 0;
+                        text: "Anim Alpha Values:"
                     }
                     ListView {
                         width: geoCol.width
-                        height: root.animStackNames.length * 15
-                        visible: root.animStackNames.length > 0;
-                        model: root.animStackNames
+                        height: root.animAlphaValues.length * 15
+                        visible: root.animAlphaValues.length > 0;
+                        model: root.animAlphaValues
                         delegate: StatText {
-                            text: modelData.length > 30
-                                ?  modelData.substring(0, 5) + "..." + modelData.substring(modelData.length - 22)
-                                : modelData
+                            text: {
+                                var actualText = modelData.split("|")[1];
+                                if (actualText) {
+                                    if (actualText.length > 30) {
+                                        return actualText.substring(0, 5) + "..." + actualText.substring(actualText.length - 22);
+                                    } else {
+                                        return actualText;
+                                    }
+                                } else {
+                                    return modelData;
+                                }
+                            }
+                            color: {
+                                var grayScale = parseFloat(modelData.split("|")[0]);
+                                return Qt.rgba(0.3 * grayScale + 0.7,
+                                               0.3 * grayScale + 0.7,
+                                               0.3 * grayScale + 0.7, 1.0);
+                            }
+                        }
+                    }
+                    StatText {
+                        visible: root.animVars.length > 0;
+                        text: "AnimVars:"
+                    }
+                    ListView {
+                        width: geoCol.width
+                        height: root.animVars.length * 15
+                        visible: root.animVars.length > 0;
+                        model: root.animVars
+                        delegate: StatText {
+                            text: {
+                                var actualText = modelData.split("|")[1];
+                                if (actualText) {
+                                    if (actualText.length > 30) {
+                                        return actualText.substring(0, 5) + "..." + actualText.substring(actualText.length - 22);
+                                    } else {
+                                        return actualText;
+                                    }
+                                } else {
+                                    return modelData;
+                                }
+                            }
+                            color: {
+                                var grayScale = parseFloat(modelData.split("|")[0]);
+                                return Qt.rgba(0.3 * grayScale + 0.7,
+                                               0.3 * grayScale + 0.7,
+                                               0.3 * grayScale + 0.7, 1.0);
+                            }
                         }
                     }
                     StatText {
diff --git a/interface/src/ui/Stats.cpp b/interface/src/ui/Stats.cpp
index 1b26c9b621..62e44645b9 100644
--- a/interface/src/ui/Stats.cpp
+++ b/interface/src/ui/Stats.cpp
@@ -207,13 +207,94 @@ void Stats::updateStats(bool force) {
 
     // Third column, avatar stats
     auto myAvatar = avatarManager->getMyAvatar();
-    auto animStack = myAvatar->getSkeletonModel()->getRig().getAnimStack();
+    auto debugAlphaMap = myAvatar->getSkeletonModel()->getRig().getDebugAlphaMap();
 
-    _animStackNames.clear();
-    for (auto animStackIterator = animStack.begin(); animStackIterator != animStack.end(); ++animStackIterator) {
-        _animStackNames << animStackIterator->first + ":   " +  QString::number(animStackIterator->second,'f',3);
+    // update animation debug alpha values
+    QStringList newAnimAlphaValues;
+    qint64 now = usecTimestampNow();
+    for (auto& iter : debugAlphaMap) {
+        QString key = iter.first;
+        float alpha = std::get<0>(iter.second);
+
+        auto prevIter = _prevDebugAlphaMap.find(key);
+        if (prevIter != _prevDebugAlphaMap.end()) {
+            float prevAlpha = std::get<0>(iter.second);
+            if (prevAlpha != alpha) {
+                // change detected: reset timer
+                _animAlphaValueChangedTimers[key] = now;
+            }
+        } else {
+            // new value: start timer
+            _animAlphaValueChangedTimers[key] = now;
+        }
+
+        AnimNodeType type = std::get<1>(iter.second);
+        if (type == AnimNodeType::Clip) {
+
+            // figure out the grayScale color of this line.
+            const float LIT_TIME = 2.0f;
+            const float FADE_OUT_TIME = 1.0f;
+            float grayScale = 0.0f;
+            float secondsElapsed = (float)(now - _animAlphaValueChangedTimers[key]) / (float)USECS_PER_SECOND;
+            if (secondsElapsed < LIT_TIME) {
+                grayScale = 1.0f;
+            } else if (secondsElapsed < LIT_TIME + FADE_OUT_TIME) {
+                grayScale = (LIT_TIME - (secondsElapsed - FADE_OUT_TIME)) / LIT_TIME;
+            } else {
+                grayScale = 0.0f;
+            }
+
+            if (grayScale > 0.0f) {
+                // append grayScaleColor to start of debug string
+                newAnimAlphaValues << QString::number(grayScale, 'f', 2) + "|" + key + ": " + QString::number(alpha, 'f', 3);
+            }
+        }
     }
-    emit animStackNamesChanged();
+
+    _animAlphaValues = newAnimAlphaValues;
+    _prevDebugAlphaMap = debugAlphaMap;
+
+    emit animAlphaValuesChanged();
+
+    // update animation anim vars
+    _animVarsList.clear();
+    auto animVars = myAvatar->getSkeletonModel()->getRig().getAnimVars().toDebugMap();
+    for (auto& iter : animVars) {
+        QString key = iter.first;
+        QString value = iter.second;
+
+        auto prevIter = _prevAnimVars.find(key);
+        if (prevIter != _prevAnimVars.end()) {
+            QString prevValue = prevIter->second;
+            if (value != prevValue) {
+                // change detected: reset timer
+                _animVarChangedTimers[key] = now;
+            }
+        } else {
+            // new value: start timer
+            _animVarChangedTimers[key] = now;
+        }
+
+        // figure out the grayScale color of this line.
+        const float LIT_TIME = 2.0f;
+        const float FADE_OUT_TIME = 0.5f;
+        float grayScale = 0.0f;
+        float secondsElapsed = (float)(now - _animVarChangedTimers[key]) / (float)USECS_PER_SECOND;
+        if (secondsElapsed < LIT_TIME) {
+            grayScale = 1.0f;
+        } else if (secondsElapsed < LIT_TIME + FADE_OUT_TIME) {
+            grayScale = (LIT_TIME - (secondsElapsed - FADE_OUT_TIME)) / LIT_TIME;
+        } else {
+            grayScale = 0.0f;
+        }
+
+        if (grayScale > 0.0f) {
+            // append grayScaleColor to start of debug string
+            _animVarsList << QString::number(grayScale, 'f', 2) + "|" + key + ": " + value;
+        }
+    }
+    _prevAnimVars = animVars;
+    emit animVarsChanged();
 
     glm::vec3 avatarPos = myAvatar->getWorldPosition();
     STAT_UPDATE(position, QVector3D(avatarPos.x, avatarPos.y, avatarPos.z));
@@ -347,6 +428,7 @@ void Stats::updateStats(bool force) {
         }
         sendingModeStream << "] " << serverCount << " servers";
         if (movingServerCount > 0) {
+
             sendingModeStream << " <SCENE NOT STABLE>";
         } else {
             sendingModeStream << " <SCENE STABLE>";
diff --git a/interface/src/ui/Stats.h b/interface/src/ui/Stats.h
index a0453a09c5..3e71c75da1 100644
--- a/interface/src/ui/Stats.h
+++ b/interface/src/ui/Stats.h
@@ -14,6 +14,7 @@
 #include <OffscreenQmlElement.h>
 #include <AudioIOStats.h>
 #include <render/Args.h>
+#include <AnimContext.h>
 
 #define STATS_PROPERTY(type, name, initialValue) \
     Q_PROPERTY(type name READ name NOTIFY name##Changed) \
@@ -134,7 +135,6 @@ private: \
  * @property {number} batchFrameTime - <em>Read-only.</em>
  * @property {number} engineFrameTime - <em>Read-only.</em>
  * @property {number} avatarSimulationTime - <em>Read-only.</em>
- * @property {string[]} animStackNames - <em>Read-only.</em>
  *
  *
  * @property {number} x
@@ -292,7 +292,8 @@ class Stats : public QQuickItem {
     STATS_PROPERTY(float, batchFrameTime, 0)
     STATS_PROPERTY(float, engineFrameTime, 0)
     STATS_PROPERTY(float, avatarSimulationTime, 0)
-    Q_PROPERTY(QStringList animStackNames READ animStackNames NOTIFY animStackNamesChanged)
+    Q_PROPERTY(QStringList animAlphaValues READ animAlphaValues NOTIFY animAlphaValuesChanged)
+    Q_PROPERTY(QStringList animVars READ animVars NOTIFY animVarsChanged)
 
     STATS_PROPERTY(int, stylusPicksCount, 0)
     STATS_PROPERTY(int, rayPicksCount, 0)
@@ -326,7 +327,8 @@ public:
     }
 
     QStringList downloadUrls () { return _downloadUrls; }
-    QStringList animStackNames() { return _animStackNames; }
+    QStringList animAlphaValues() { return _animAlphaValues; }
+    QStringList animVars() { return _animVarsList; }
 
 public slots:
     void forceUpdateStats() { updateStats(true); }
@@ -1028,12 +1030,8 @@ signals:
      */
     void avatarSimulationTimeChanged();
 
-    /**jsdoc
-    * Triggered when the value of the <code>animStackNames</code> property changes.
-    * @function Stats.animStackNamesChanged
-    * @returns {Signal}
-    */
-    void animStackNamesChanged();
+    void animAlphaValuesChanged();
+    void animVarsChanged();
 
     /**jsdoc
      * Triggered when the value of the <code>rectifiedTextureCount</code> property changes.
@@ -1336,7 +1334,14 @@ private:
     QString _monospaceFont;
     const AudioIOStats* _audioStats;
     QStringList _downloadUrls = QStringList();
-    QStringList _animStackNames = QStringList();
+
+    QStringList _animAlphaValues = QStringList();
+    AnimContext::DebugAlphaMap _prevDebugAlphaMap;  // alpha values from previous frame
+    std::map<QString, qint64> _animAlphaValueChangedTimers; // last time alpha value has changed
+
+    QStringList _animVarsList = QStringList();
+    std::map<QString, QString> _prevAnimVars;  // anim vars from previous frame
+    std::map<QString, qint64> _animVarChangedTimers; // last time animVar value has changed.
 };
 
 #endif // hifi_Stats_h
diff --git a/libraries/animation/src/AnimBlendLinear.cpp b/libraries/animation/src/AnimBlendLinear.cpp
index e2d79f864d..17ca88123f 100644
--- a/libraries/animation/src/AnimBlendLinear.cpp
+++ b/libraries/animation/src/AnimBlendLinear.cpp
@@ -27,7 +27,7 @@ AnimBlendLinear::~AnimBlendLinear() {
 const AnimPoseVec& AnimBlendLinear::evaluate(const AnimVariantMap& animVars, const AnimContext& context, float dt, AnimVariantMap& triggersOut) {
 
     _alpha = animVars.lookup(_alphaVar, _alpha);
-    float parentAlpha = _animStack[_id];
+    float parentDebugAlpha = context.getDebugAlpha(_id);
 
     if (_children.size() == 0) {
         for (auto&& pose : _poses) {
@@ -35,7 +35,7 @@ const AnimPoseVec& AnimBlendLinear::evaluate(const AnimVariantMap& animVars, con
         }
     } else if (_children.size() == 1) {
         _poses = _children[0]->evaluate(animVars, context, dt, triggersOut);
-        _animStack[_children[0]->getID()] = parentAlpha;
+        context.setDebugAlpha(_children[0]->getID(), parentDebugAlpha, _children[0]->getType());
     } else {
         float clampedAlpha = glm::clamp(_alpha, 0.0f, (float)(_children.size() - 1));
         size_t prevPoseIndex = glm::floor(clampedAlpha);
@@ -48,12 +48,12 @@ const AnimPoseVec& AnimBlendLinear::evaluate(const AnimVariantMap& animVars, con
         float weight2 = 0.0f;
         if (prevPoseIndex == nextPoseIndex) {
             weight2 = 1.0f;
-            _animStack[_children[nextPoseIndex]->getID()] = weight2 * parentAlpha;
+            context.setDebugAlpha(_children[nextPoseIndex]->getID(), weight2 * parentDebugAlpha, _children[nextPoseIndex]->getType());
         } else {
             weight2 = alpha;
             weight1 = 1.0f - weight2;
-            _animStack[_children[prevPoseIndex]->getID()] = weight1 * parentAlpha;
-            _animStack[_children[nextPoseIndex]->getID()] = weight2 * parentAlpha;
+            context.setDebugAlpha(_children[prevPoseIndex]->getID(), weight1 * parentDebugAlpha, _children[prevPoseIndex]->getType());
+            context.setDebugAlpha(_children[nextPoseIndex]->getID(), weight2 * parentDebugAlpha, _children[nextPoseIndex]->getType());
         }
     }
     processOutputJoints(triggersOut);
diff --git a/libraries/animation/src/AnimBlendLinearMove.cpp b/libraries/animation/src/AnimBlendLinearMove.cpp
index 42098eb072..07e1c17f77 100644
--- a/libraries/animation/src/AnimBlendLinearMove.cpp
+++ b/libraries/animation/src/AnimBlendLinearMove.cpp
@@ -62,9 +62,7 @@ const AnimPoseVec& AnimBlendLinearMove::evaluate(const AnimVariantMap& animVars,
         speed = animVars.lookup("moveForwardSpeed", speed);
     }
     _alpha = calculateAlpha(speed, _characteristicSpeeds);
-    float parentAlpha = _animStack[_id];
-
-    _animStack["speed"] = speed;
+    float parentDebugAlpha = context.getDebugAlpha(_id);
 
     if (_children.size() == 0) {
         for (auto&& pose : _poses) {
@@ -77,7 +75,7 @@ const AnimPoseVec& AnimBlendLinearMove::evaluate(const AnimVariantMap& animVars,
         float prevDeltaTime, nextDeltaTime;
         setFrameAndPhase(dt, alpha, prevPoseIndex, nextPoseIndex, &prevDeltaTime, &nextDeltaTime, triggersOut);
         evaluateAndBlendChildren(animVars, context, triggersOut, alpha, prevPoseIndex, nextPoseIndex, prevDeltaTime, nextDeltaTime);
-        _animStack[_children[0]->getID()] = parentAlpha;
+        context.setDebugAlpha(_children[0]->getID(), parentDebugAlpha, _children[0]->getType());
     } else {
         auto clampedAlpha = glm::clamp(_alpha, 0.0f, (float)(_children.size() - 1));
         auto prevPoseIndex = glm::floor(clampedAlpha);
@@ -87,17 +85,11 @@ const AnimPoseVec& AnimBlendLinearMove::evaluate(const AnimVariantMap& animVars,
         setFrameAndPhase(dt, alpha, prevPoseIndex, nextPoseIndex, &prevDeltaTime, &nextDeltaTime, triggersOut);
         evaluateAndBlendChildren(animVars, context, triggersOut, alpha, prevPoseIndex, nextPoseIndex, prevDeltaTime, nextDeltaTime);
 
-        // weights are for animation stack debug purposes only.
-        float weight1 = 0.0f;
-        float weight2 = 0.0f;
         if (prevPoseIndex == nextPoseIndex) {
-            weight2 = 1.0f;
-            _animStack[_children[nextPoseIndex]->getID()] = weight2 * parentAlpha;
+            context.setDebugAlpha(_children[nextPoseIndex]->getID(), parentDebugAlpha, _children[nextPoseIndex]->getType());
         } else {
-            weight2 = alpha;
-            weight1 = 1.0f - weight2;
-            _animStack[_children[prevPoseIndex]->getID()] = weight1 * parentAlpha;
-            _animStack[_children[nextPoseIndex]->getID()] = weight2 * parentAlpha;
+            context.setDebugAlpha(_children[prevPoseIndex]->getID(), (1.0f - alpha) * parentDebugAlpha, _children[prevPoseIndex]->getType());
+            context.setDebugAlpha(_children[nextPoseIndex]->getID(), alpha * parentDebugAlpha, _children[nextPoseIndex]->getType());
         }
     }
 
diff --git a/libraries/animation/src/AnimContext.h b/libraries/animation/src/AnimContext.h
index e8bf5c34eb..ecfb94a28e 100644
--- a/libraries/animation/src/AnimContext.h
+++ b/libraries/animation/src/AnimContext.h
@@ -14,8 +14,27 @@
 #include <glm/glm.hpp>
 #include <glm/gtc/quaternion.hpp>
 
+#include <QString.h>
+#include <QStringList.h>
+#include <map>
+
+enum class AnimNodeType {
+    Clip = 0,
+    BlendLinear,
+    BlendLinearMove,
+    Overlay,
+    StateMachine,
+    Manipulator,
+    InverseKinematics,
+    DefaultPose,
+    TwoBoneIK,
+    PoleVectorConstraint,
+    NumTypes
+};
+
 class AnimContext {
 public:
+    AnimContext() {}
     AnimContext(bool enableDebugDrawIKTargets, bool enableDebugDrawIKConstraints, bool enableDebugDrawIKChains,
                 const glm::mat4& geometryToRigMatrix, const glm::mat4& rigToWorldMatrix);
 
@@ -25,6 +44,26 @@ public:
     const glm::mat4& getGeometryToRigMatrix() const { return _geometryToRigMatrix; }
     const glm::mat4& getRigToWorldMatrix() const { return _rigToWorldMatrix; }
 
+    float getDebugAlpha(const QString& key) const {
+        auto it = _debugAlphaMap.find(key);
+        if (it != _debugAlphaMap.end()) {
+            return std::get<0>(it->second);
+        } else {
+            return 1.0f;
+        }
+    }
+
+    using DebugAlphaMapValue = std::tuple<float, AnimNodeType>;
+    using DebugAlphaMap = std::map<QString, DebugAlphaMapValue>;
+
+    void setDebugAlpha(const QString& key, float alpha, AnimNodeType type) const {
+        _debugAlphaMap[key] = DebugAlphaMapValue(alpha, type);
+    }
+
+    const DebugAlphaMap& getDebugAlphaMap() const {
+        return _debugAlphaMap;
+    }
+
 protected:
 
     bool _enableDebugDrawIKTargets { false };
@@ -32,6 +71,9 @@ protected:
     bool _enableDebugDrawIKChains { false };
     glm::mat4 _geometryToRigMatrix;
     glm::mat4 _rigToWorldMatrix;
+
+    // used for debugging internal state of animation system.
+    mutable DebugAlphaMap _debugAlphaMap;
 };
 
 #endif  // hifi_AnimContext_h
diff --git a/libraries/animation/src/AnimNode.cpp b/libraries/animation/src/AnimNode.cpp
index a8e76617ae..f055e6b473 100644
--- a/libraries/animation/src/AnimNode.cpp
+++ b/libraries/animation/src/AnimNode.cpp
@@ -12,10 +12,6 @@
 
 #include <QtGlobal>
 
-std::map<QString, float> AnimNode::_animStack = {
-    {"none", 0.0f}
-};
-
 AnimNode::Pointer AnimNode::getParent() {
     return _parent.lock();
 }
diff --git a/libraries/animation/src/AnimNode.h b/libraries/animation/src/AnimNode.h
index 1f14889ce4..1a12bb8ddb 100644
--- a/libraries/animation/src/AnimNode.h
+++ b/libraries/animation/src/AnimNode.h
@@ -36,19 +36,7 @@ class QJsonObject;
 
 class AnimNode : public std::enable_shared_from_this<AnimNode> {
 public:
-    enum class Type {
-        Clip = 0,
-        BlendLinear,
-        BlendLinearMove,
-        Overlay,
-        StateMachine,
-        Manipulator,
-        InverseKinematics,
-        DefaultPose,
-        TwoBoneIK,
-        PoleVectorConstraint,
-        NumTypes
-    };
+    using Type = AnimNodeType;
     using Pointer = std::shared_ptr<AnimNode>;
     using ConstPointer = std::shared_ptr<const AnimNode>;
 
@@ -84,7 +72,6 @@ public:
     }
 
     void setCurrentFrame(float frame);
-    const std::map<QString, float> getAnimStack() { return _animStack; }
 
     template <typename F>
     bool traverse(F func) {
@@ -127,9 +114,6 @@ protected:
     std::weak_ptr<AnimNode> _parent;
     std::vector<QString> _outputJointNames;
 
-    // global available to Stats.h
-    static std::map<QString, float> _animStack;
-
     // no copies
     AnimNode(const AnimNode&) = delete;
     AnimNode& operator=(const AnimNode&) = delete;
diff --git a/libraries/animation/src/AnimStateMachine.cpp b/libraries/animation/src/AnimStateMachine.cpp
index 90fd425ae5..00ae5e6d39 100644
--- a/libraries/animation/src/AnimStateMachine.cpp
+++ b/libraries/animation/src/AnimStateMachine.cpp
@@ -23,9 +23,7 @@ AnimStateMachine::~AnimStateMachine() {
 
 const AnimPoseVec& AnimStateMachine::evaluate(const AnimVariantMap& animVars, const AnimContext& context, float dt, AnimVariantMap& triggersOut) {
 
-    if (_id.contains("userAnimStateMachine")) {
-        _animStack.clear();
-    }
+    float parentDebugAlpha = context.getDebugAlpha(_id);
 
     QString desiredStateID = animVars.lookup(_currentStateVar, _currentState->getID());
     if (_currentState->getID() != desiredStateID) {
@@ -33,8 +31,6 @@ const AnimPoseVec& AnimStateMachine::evaluate(const AnimVariantMap& animVars, co
         bool foundState = false;
         for (auto& state : _states) {
             if (state->getID() == desiredStateID) {
-                // parenthesis means previous state, which is a snapshot.
-                _previousStateID = "(" + _currentState->getID() + ")";
                 switchState(animVars, context, state);
                 foundState = true;
                 break;
@@ -48,8 +44,6 @@ const AnimPoseVec& AnimStateMachine::evaluate(const AnimVariantMap& animVars, co
     // evaluate currentState transitions
     auto desiredState = evaluateTransitions(animVars);
     if (desiredState != _currentState) {
-        // parenthesis means previous state, which is a snapshot.
-        _previousStateID = "(" + _currentState->getID() + ")";
         switchState(animVars, context, desiredState);
     }
 
@@ -57,17 +51,8 @@ const AnimPoseVec& AnimStateMachine::evaluate(const AnimVariantMap& animVars, co
     auto currentStateNode = _children[_currentState->getChildIndex()];
     assert(currentStateNode);
 
-    if (!_previousStateID.contains("none")) {
-        _animStack[_previousStateID] = 1.0f - _alpha;
-    }
-
     if (_duringInterp) {
         _alpha += _alphaVel * dt;
-        if (_alpha > 1.0f) {
-            _animStack[_currentState->getID()] = 1.0f;
-        } else {
-            _animStack[_currentState->getID()] = _alpha;
-        }
         if (_alpha < 1.0f) {
             AnimPoseVec* nextPoses = nullptr;
             AnimPoseVec* prevPoses = nullptr;
@@ -88,18 +73,16 @@ const AnimPoseVec& AnimStateMachine::evaluate(const AnimVariantMap& animVars, co
             if (_poses.size() > 0 && nextPoses && prevPoses && nextPoses->size() > 0 && prevPoses->size() > 0) {
                 ::blend(_poses.size(), &(prevPoses->at(0)), &(nextPoses->at(0)), _alpha, &_poses[0]);
             }
+            context.setDebugAlpha(_currentState->getID(), _alpha * parentDebugAlpha, _children[_currentState->getChildIndex()]->getType());
         } else {
             _duringInterp = false;
-            if (_animStack.count(_previousStateID) > 0) {
-                _animStack.erase(_previousStateID);
-            }
-            _previousStateID = "none";
             _prevPoses.clear();
             _nextPoses.clear();
         }
     }
+
     if (!_duringInterp) {
-        _animStack[_currentState->getID()] = 1.0f;
+        context.setDebugAlpha(_currentState->getID(), parentDebugAlpha, _children[_currentState->getChildIndex()]->getType());
         _poses = currentStateNode->evaluate(animVars, context, dt, triggersOut);
     }
     processOutputJoints(triggersOut);
diff --git a/libraries/animation/src/AnimStateMachine.h b/libraries/animation/src/AnimStateMachine.h
index b20e5203a1..8e1e1b7bd8 100644
--- a/libraries/animation/src/AnimStateMachine.h
+++ b/libraries/animation/src/AnimStateMachine.h
@@ -138,7 +138,6 @@ protected:
     float _alpha = 0.0f;
     AnimPoseVec _prevPoses;
     AnimPoseVec _nextPoses;
-    QString _previousStateID { "none" };
 
     State::Pointer _currentState;
     std::vector<State::Pointer> _states;
diff --git a/libraries/animation/src/AnimVariant.cpp b/libraries/animation/src/AnimVariant.cpp
index 483a7999c9..509462984a 100644
--- a/libraries/animation/src/AnimVariant.cpp
+++ b/libraries/animation/src/AnimVariant.cpp
@@ -67,6 +67,7 @@ QScriptValue AnimVariantMap::animVariantMapToScriptValue(QScriptEngine* engine,
     }
     return target;
 }
+
 void AnimVariantMap::copyVariantsFrom(const AnimVariantMap& other) {
     for (auto& pair : other._map) {
         _map[pair.first] = pair.second;
@@ -124,3 +125,43 @@ void AnimVariantMap::animVariantMapFromScriptValue(const QScriptValue& source) {
         }
     }
 }
+
+std::map<QString, QString> AnimVariantMap::toDebugMap() const {
+    std::map<QString, QString> result;
+    for (auto& pair : _map) {
+        switch (pair.second.getType()) {
+        case AnimVariant::Type::Bool:
+            result[pair.first] = QString("%1").arg(pair.second.getBool());
+            break;
+        case AnimVariant::Type::Int:
+            result[pair.first] = QString("%1").arg(pair.second.getInt());
+            break;
+        case AnimVariant::Type::Float:
+            result[pair.first] = QString::number(pair.second.getFloat(), 'f', 3);
+            break;
+        case AnimVariant::Type::Vec3: {
+            glm::vec3 value = pair.second.getVec3();
+            result[pair.first] = QString("(%1, %2, %3)").
+                arg(QString::number(value.x, 'f', 3)).
+                arg(QString::number(value.y, 'f', 3)).
+                arg(QString::number(value.z, 'f', 3));
+            break;
+        }
+        case AnimVariant::Type::Quat: {
+            glm::quat value = pair.second.getQuat();
+            result[pair.first] = QString("(%1, %2, %3, %4)").
+                arg(QString::number(value.x, 'f', 3)).
+                arg(QString::number(value.y, 'f', 3)).
+                arg(QString::number(value.z, 'f', 3)).
+                arg(QString::number(value.w, 'f', 3));
+            break;
+        }
+        case AnimVariant::Type::String:
+            result[pair.first] = pair.second.getString();
+            break;
+        default:
+            assert(("invalid AnimVariant::Type", false));
+        }
+    }
+    return result;
+}
diff --git a/libraries/animation/src/AnimVariant.h b/libraries/animation/src/AnimVariant.h
index d383b5abb8..0f921984b1 100644
--- a/libraries/animation/src/AnimVariant.h
+++ b/libraries/animation/src/AnimVariant.h
@@ -235,6 +235,9 @@ public:
     void animVariantMapFromScriptValue(const QScriptValue& object);
     void copyVariantsFrom(const AnimVariantMap& other);
 
+    // For stat debugging.
+    std::map<QString, QString> toDebugMap() const;
+
 #ifdef NDEBUG
     void dump() const {
         qCDebug(animation) << "AnimVariantMap =";
diff --git a/libraries/animation/src/Rig.cpp b/libraries/animation/src/Rig.cpp
index 13cf165dac..91d4e0f9d3 100644
--- a/libraries/animation/src/Rig.cpp
+++ b/libraries/animation/src/Rig.cpp
@@ -1061,8 +1061,10 @@ void Rig::updateAnimations(float deltaTime, const glm::mat4& rootTransform, cons
             // animations haven't fully loaded yet.
             _internalPoseSet._relativePoses = _animSkeleton->getRelativeDefaultPoses();
         }
+        _lastAnimVars = _animVars;
         _animVars.clearTriggers();
         _animVars = triggersOut;
+        _lastContext = context;
     }
     applyOverridePoses();
     buildAbsoluteRigPoses(_internalPoseSet._relativePoses, _internalPoseSet._absolutePoses);
diff --git a/libraries/animation/src/Rig.h b/libraries/animation/src/Rig.h
index accbcccbbc..95a4b6f40d 100644
--- a/libraries/animation/src/Rig.h
+++ b/libraries/animation/src/Rig.h
@@ -222,7 +222,9 @@ public:
     // input assumed to be in rig space
     void computeHeadFromHMD(const AnimPose& hmdPose, glm::vec3& headPositionOut, glm::quat& headOrientationOut) const;
 
-    const std::map<QString, float> getAnimStack() { return _animNode->getAnimStack(); }
+    // used to debug animation playback
+    const AnimContext::DebugAlphaMap& getDebugAlphaMap() const { return _lastContext.getDebugAlphaMap(); }
+    const AnimVariantMap& getAnimVars() const { return _lastAnimVars; }
 
     void toggleSmoothPoleVectors() { _smoothPoleVectors = !_smoothPoleVectors; };
 signals:
@@ -388,6 +390,9 @@ protected:
 
     int _rigId;
     bool _headEnabled { false };
+
+    AnimContext _lastContext;
+    AnimVariantMap _lastAnimVars;
 };
 
 #endif /* defined(__hifi__Rig__) */