diff --git a/src/AnimNode.h b/src/AnimNode.h
index 283fda0..bdf8184 100644
--- a/src/AnimNode.h
+++ b/src/AnimNode.h
@@ -9,28 +9,42 @@
 
 #include "AnimationController.h"
 
-struct AnimNode {
-  AnimNode(AnimationController* animation_controller) : m_animation_controller(animation_controller) {}
-  virtual ~AnimNode() {};
+enum class AnimNodeType {
+  Blend,
+  SpeedScale,
+  AnimSampler
+};
 
+struct AnimNode {
+  AnimNode(AnimationController* animation_controller)
+      : m_animation_controller(animation_controller),
+        m_current_time(0.f),
+        m_is_time_synced(false),
+        m_anim_duration(0.f) {}
+  virtual ~AnimNode(){};
+
+  AnimNodeType m_anim_node_type;
   std::string m_name;
   float m_current_time;
+  bool m_is_time_synced;
+  float m_anim_duration;
   AnimationController* m_animation_controller;
   ozz::vector<ozz::math::SoaTransform> m_local_matrices;
 
-  virtual void Reset() {
-    m_current_time = 0.f;
-  }
+  virtual void Reset() { m_current_time = 0.f; }
 
-  virtual void Update(float dt) {
-    m_current_time += dt;
-  }
+  virtual void UpdateIsSynced(bool is_synced) = 0;
 
-  virtual void Evaluate(ozz::vector<ozz::math::SoaTransform>* local_matrices) = 0;
+  virtual void EvalAnimDuration() = 0;
 
-  virtual void CollectNodeOrdering (std::vector<AnimNode*>& anim_nodes) = 0;
+  virtual void UpdateTime(float dt) { m_current_time += dt; }
 
-  virtual void DrawDebugUi() {};
+  virtual void Evaluate(
+      ozz::vector<ozz::math::SoaTransform>* local_matrices) = 0;
+
+  virtual void CollectNodeOrdering(std::vector<AnimNode*>& anim_nodes) = 0;
+
+  virtual void DrawDebugUi(){};
 };
 
 #endif  //ANIMTESTBED_ANIMNODE_H
diff --git a/src/AnimNodes/AnimSamplerNode.h b/src/AnimNodes/AnimSamplerNode.h
index 5746cb7..ab07938 100644
--- a/src/AnimNodes/AnimSamplerNode.h
+++ b/src/AnimNodes/AnimSamplerNode.h
@@ -10,26 +10,47 @@
 struct AnimSamplerNode : public AnimNode {
   AnimSamplerNode(AnimationController* animation_controller)
       : AnimNode(animation_controller),
-        m_anim_ratio(0.f),
-        m_override_ratio(false){};
+        m_override_ratio(false),
+        m_anim_ratio(0.f) {
+    assert(m_current_time < 100.0f);
+    m_anim_node_type = AnimNodeType::AnimSampler;
+  };
   virtual ~AnimSamplerNode() {}
 
   ozz::animation::Animation* m_animation;
 
-  float m_anim_ratio;
   bool m_override_ratio;
+  float m_anim_ratio;
 
   ozz::animation::SamplingCache m_sampling_cache;
 
   void SetAnimation(ozz::animation::Animation* animation);
 
-  virtual void Update(float dt) override {
+  virtual void UpdateIsSynced(bool is_synced) override {
+    m_is_time_synced = is_synced;
+  }
+
+  virtual void EvalAnimDuration() override {
+    m_anim_duration = m_animation->duration();
+  }
+
+  virtual void UpdateTime(float dt) override {
     m_current_time += dt;
     if (!m_override_ratio) {
-      const float duration = m_animation->duration();
-      m_anim_ratio = fmodf((float)m_current_time / duration, 1.0f);
+      if (m_is_time_synced) {
+        m_anim_ratio = fmodf((float)m_current_time, 1.0f);
+        m_current_time = m_anim_ratio;
+      } else {
+        const float duration = m_animation->duration();
+        m_anim_ratio = fmodf((float)m_current_time / duration, 1.0f);
+      }
+    }
+
+    if (m_anim_ratio < 0.f) {
+      m_anim_ratio += 1.0f;
     }
   }
+
   virtual void Evaluate(
       ozz::vector<ozz::math::SoaTransform>* local_matrices) override;
 
diff --git a/src/AnimNodes/BlendNode.cc b/src/AnimNodes/BlendNode.cc
index 4e4a6e3..75ecac7 100644
--- a/src/AnimNodes/BlendNode.cc
+++ b/src/AnimNodes/BlendNode.cc
@@ -13,7 +13,9 @@ BlendNode::BlendNode(AnimationController* animation_controller)
     : AnimNode(animation_controller),
       m_input_A(nullptr),
       m_input_B(nullptr),
-      m_weight(0.f) {
+      m_weight(0.f),
+      m_sync_inputs(false) {
+  m_anim_node_type = AnimNodeType::Blend;
   const SkinnedMesh* skinned_mesh = m_animation_controller->m_skinned_mesh;
   const int num_soa_joints = skinned_mesh->m_skeleton.num_soa_joints();
   const int num_joints = skinned_mesh->m_skeleton.num_joints();
@@ -54,6 +56,7 @@ void BlendNode::DrawDebugUi() {
     ImGui::Text("Input B:");
     m_input_B->DrawDebugUi();
     ImGui::SliderFloat("Weight", &m_weight, 0.f, 1.f);
+    ImGui::Checkbox("Sync Inputs", &m_sync_inputs);
     ImGui::TreePop();
   }
 }
diff --git a/src/AnimNodes/BlendNode.h b/src/AnimNodes/BlendNode.h
index dff4bf5..49be09d 100644
--- a/src/AnimNodes/BlendNode.h
+++ b/src/AnimNodes/BlendNode.h
@@ -9,11 +9,13 @@
 
 struct BlendNode : public AnimNode {
   BlendNode(AnimationController* animation_controller);
+
   virtual ~BlendNode() {}
 
   AnimNode* m_input_A;
   AnimNode* m_input_B;
   float m_weight;
+  bool m_sync_inputs;
 
   ozz::vector<ozz::math::SoaTransform> m_local_matrices_A;
   ozz::vector<ozz::math::SoaTransform> m_local_matrices_B;
@@ -22,9 +24,37 @@ struct BlendNode : public AnimNode {
     m_current_time = 0.f;
   }
 
-  virtual void Update(float dt) {
-    m_input_A->Update(dt);
-    m_input_B->Update(dt);
+  virtual void UpdateIsSynced(bool is_synced) override {
+    m_is_time_synced = is_synced;
+
+    if (m_sync_inputs) {
+      m_is_time_synced = true;
+    }
+
+    m_input_B->UpdateIsSynced(m_is_time_synced);
+    m_input_A->UpdateIsSynced(m_is_time_synced);
+  }
+
+  virtual void EvalAnimDuration() override {
+    if (m_is_time_synced) {
+      m_anim_duration = (1.0f - m_weight) * m_input_A->m_anim_duration + m_weight * m_input_B->m_anim_duration;
+    } else {
+      assert (false);
+    }
+  }
+
+  virtual void UpdateTime(float dt) {
+    if (m_is_time_synced) {
+      float current_time_absolute = m_current_time * m_anim_duration + dt;
+      m_current_time = fmodf(current_time_absolute / m_anim_duration, 1.0);
+
+      m_input_A->UpdateTime(m_current_time - m_input_A->m_current_time);
+      m_input_B->UpdateTime(m_current_time - m_input_B->m_current_time);
+    } else {
+      m_current_time += dt;
+      m_input_A->UpdateTime(dt);
+      m_input_B->UpdateTime(dt);
+    }
   }
 
   virtual void Evaluate(
diff --git a/src/AnimNodes/SpeedScaleNode.cc b/src/AnimNodes/SpeedScaleNode.cc
index c755488..0dcc4e1 100644
--- a/src/AnimNodes/SpeedScaleNode.cc
+++ b/src/AnimNodes/SpeedScaleNode.cc
@@ -9,7 +9,16 @@
 void SpeedScaleNode::DrawDebugUi() {
   std::string node_name = "SpeedScaleNode: " + m_name;
   if (ImGui::TreeNode(node_name.c_str())) {
-    ImGui::SliderFloat("Time Scale", &m_time_scale, -5.f, 5.f);
+    bool is_negative = m_time_scale < 0.f;
+    if (ImGui::Checkbox("Reverse Time", &is_negative)) {
+      m_time_scale = m_time_scale * -1.f;
+    }
+
+    // ensure m_time_scale is positive
+    m_time_scale = m_time_scale * (is_negative ? -1.f : 1.f);
+    ImGui::SliderFloat("Time Scale", &m_time_scale, 0.01f, 5.f);
+    // and back to the original negative or positive sign
+    m_time_scale = m_time_scale * (is_negative ? -1.f : 1.f);
 
     m_input_node->DrawDebugUi();
 
diff --git a/src/AnimNodes/SpeedScaleNode.h b/src/AnimNodes/SpeedScaleNode.h
index 6d614d6..1b11d39 100644
--- a/src/AnimNodes/SpeedScaleNode.h
+++ b/src/AnimNodes/SpeedScaleNode.h
@@ -8,25 +8,43 @@
 #include "../AnimNode.h"
 
 struct SpeedScaleNode : public AnimNode {
-  SpeedScaleNode(AnimationController* animation_controller): AnimNode (animation_controller), m_time_scale(1.f) {}
+  SpeedScaleNode(AnimationController* animation_controller)
+      : AnimNode(animation_controller), m_time_scale(1.f) {
+    m_anim_node_type = AnimNodeType::SpeedScale;
+  }
 
   float m_time_scale;
   AnimNode* m_input_node;
 
-  virtual void Reset() {
-    m_current_time = 0.f;
+  virtual void Reset() { m_current_time = 0.f; }
+
+  virtual void UpdateIsSynced(bool is_synced) override {
+    m_is_time_synced = is_synced;
+    m_input_node->UpdateIsSynced(is_synced);
   }
 
-  virtual void Update(float dt) {
-    m_current_time += dt * m_time_scale;
-    m_input_node->Update(dt * m_time_scale);
+  virtual void EvalAnimDuration() override {
+    assert(fabs(m_time_scale) >= 0.01f);
+    m_anim_duration = fabsf(m_input_node->m_anim_duration / m_time_scale);
   }
 
-  virtual void Evaluate(ozz::vector<ozz::math::SoaTransform>* local_matrices) override {
+  virtual void UpdateTime(float dt) {
+    if (!m_is_time_synced) {
+      m_current_time += dt * m_time_scale;
+      m_input_node->UpdateTime(dt * m_time_scale);
+    } else {
+      m_current_time += dt;
+      m_input_node->UpdateTime(dt);
+    }
+  }
+
+  virtual void Evaluate(
+      ozz::vector<ozz::math::SoaTransform>* local_matrices) override {
     m_input_node->Evaluate(local_matrices);
   };
 
-  virtual void CollectNodeOrdering (std::vector<AnimNode*>& anim_nodes) override {
+  virtual void CollectNodeOrdering(
+      std::vector<AnimNode*>& anim_nodes) override {
     anim_nodes.push_back(this);
     m_input_node->CollectNodeOrdering(anim_nodes);
   }
diff --git a/src/AnimationController.cc b/src/AnimationController.cc
index baa819d..e2abbc2 100644
--- a/src/AnimationController.cc
+++ b/src/AnimationController.cc
@@ -33,7 +33,7 @@ AnimationController::AnimationController(SkinnedMesh* skinned_mesh)
   m_anim_nodes.push_back(sampler_node0);
 
   AnimSamplerNode* sampler_node1 = new AnimSamplerNode(this);
-  sampler_node1->m_name = "AnimSampler0";
+  sampler_node1->m_name = "AnimSampler1";
   sampler_node1->SetAnimation(skinned_mesh->m_animations[2]);
   m_anim_nodes.push_back(sampler_node1);
 
@@ -46,13 +46,18 @@ AnimationController::AnimationController(SkinnedMesh* skinned_mesh)
   blend_node->m_name = "Blend0";
   blend_node->m_input_A = speed_node;
   blend_node->m_input_B = sampler_node1;
+  blend_node->m_sync_inputs = true;
   m_anim_nodes.push_back(blend_node);
 
-  m_output_node = blend_node;
+  SpeedScaleNode* speed_node1 = new SpeedScaleNode(this);
+  speed_node1->m_name = "SpeedNode1";
+  speed_node1->m_input_node = blend_node;
+  m_anim_nodes.push_back(speed_node1);
+
+  m_output_node = speed_node1;
 
   m_output_node->CollectNodeOrdering(m_ordered_nodes);
 
-  std::cout << "Have " << m_ordered_nodes.size() << " nodes in blend tree." << std::endl;
   m_output_node->Reset();
 }
 
@@ -67,14 +72,27 @@ AnimationController::~AnimationController() {
   m_output_node = nullptr;
 }
 
-
+void AnimationController::ResetAnims() {
+  for (int i = 0; i < m_ordered_nodes.size(); i++) {
+    m_ordered_nodes[i]->Reset();
+  }
+}
 
 void AnimationController::Update(float dt) {
   if (m_output_node == nullptr) {
     return;
   }
 
-  m_output_node->Update(dt);
+  m_output_node->UpdateIsSynced(false);
+
+  for (int i = m_ordered_nodes.size() - 1; i >= 0; i--) {
+    AnimNode* node = m_ordered_nodes[i];
+    if (node->m_is_time_synced) {
+      node->EvalAnimDuration();
+    }
+  }
+
+  m_output_node->UpdateTime(dt);
 }
 
 
@@ -96,7 +114,13 @@ void AnimationController::Evaluate() {
 
 
 void AnimationController::DrawDebugUi() {
+  ImGui::SetNextWindowSize(ImVec2(500, 300), ImGuiCond_FirstUseEver);
   ImGui::Begin("AnimationController");
+
+  if (ImGui::Button("Reset")) {
+    ResetAnims();
+  }
+
   if (m_output_node && ImGui::TreeNode("Output")) {
     m_output_node->DrawDebugUi();
 
@@ -104,10 +128,37 @@ void AnimationController::DrawDebugUi() {
   }
 
   if (m_output_node && ImGui::TreeNode("Nodes")) {
+    ImGui::Columns(4, "NodeOverview"); // 4-ways, with border
+    ImGui::Separator();
+    ImGui::Text("Name"); ImGui::NextColumn();
+    ImGui::Text("Synced"); ImGui::NextColumn();
+    ImGui::Text("Duration"); ImGui::NextColumn();
+    ImGui::Text("Time"); ImGui::NextColumn();
+
+    ImGui::Separator();
+    static int selected = -1;
+
     for (int i = 0; i < m_ordered_nodes.size(); i++) {
-      ImGui::Text(m_ordered_nodes[i]->m_name.c_str());
+      AnimNode* node = m_ordered_nodes[i];
+      if (ImGui::Selectable(node->m_name.c_str(), selected == i, ImGuiSelectableFlags_SpanAllColumns))
+        selected = i;
+      bool hovered = ImGui::IsItemHovered();
+      ImGui::NextColumn();
+
+      ImGui::Text(node->m_is_time_synced ? "X" : "-"); ImGui::NextColumn();
+
+      ImGui::PushID((void*)&node->m_anim_duration);
+      ImGui::Text("%2.3f", node->m_anim_duration);      ImGui::NextColumn();
+      ImGui::PopID();
+
+      ImGui::PushID((void*)&node->m_current_time);
+      ImGui::Text("%2.3f", node->m_current_time);      ImGui::NextColumn();
+      ImGui::PopID();
     }
 
+    ImGui::Columns(1);
+    ImGui::Separator();
+
     ImGui::TreePop();
   }
 
diff --git a/src/AnimationController.h b/src/AnimationController.h
index c57008c..d70aa0c 100644
--- a/src/AnimationController.h
+++ b/src/AnimationController.h
@@ -22,8 +22,8 @@ struct AnimationController {
       ozz::animation::Animation* blend_anim_A,
       ozz::animation::Animation* blend_anim_B) {
   }
-  void ResetAnims() {
-  }
+  void ResetAnims();
+
   void Update(float dt);
   void Evaluate();
 
@@ -32,12 +32,9 @@ struct AnimationController {
   float m_current_time;
 
   ozz::vector<ozz::math::SoaTransform> m_local_matrices;
-  ozz::vector<ozz::math::SoaTransform> m_local_matrices_A;
-  ozz::vector<ozz::math::SoaTransform> m_local_matrices_B;
   ozz::vector<ozz::math::SoaTransform> m_local_matrices_blended;
 
   ozz::animation::SamplingCache m_sampling_cache_A;
-  ozz::animation::SamplingCache m_sampling_cache_B;
 
   SkinnedMesh* m_skinned_mesh = nullptr;