Update StaminaManager

src/main/java/emu/grasscutter/game/managers/StaminaManager/AfterUpdateStaminaListener.java

+package emu.grasscutter.game.managers.StaminaManager;
+
+public interface AfterUpdateStaminaListener {
+    /**
+     * onBeforeUpdateStamina() will be called before StaminaManager attempt to update the player's current stamina.
+     * This gives listeners a chance to intercept this update.
+     *
+     * @param reason     Why updating stamina.
+     * @param newStamina New Stamina value.
+     */
+    void onAfterUpdateStamina(String reason, int newStamina);
+}

src/main/java/emu/grasscutter/game/managers/StaminaManager/BeforeUpdateStaminaListener.java

+package emu.grasscutter.game.managers.StaminaManager;
+
+public interface BeforeUpdateStaminaListener {
+    /**
+     * onBeforeUpdateStamina() will be called before StaminaManager attempt to update the player's current stamina.
+     * This gives listeners a chance to intercept this update.
+     * @param reason Why updating stamina.
+     * @param newStamina New ABSOLUTE stamina value.
+     * @return true if you want to cancel this update, otherwise false.
+     */
+    int onBeforeUpdateStamina(String reason, int newStamina);
+    /**
+     * onBeforeUpdateStamina() will be called before StaminaManager attempt to update the player's current stamina.
+     * This gives listeners a chance to intercept this update.
+     * @param reason Why updating stamina.
+     * @param consumption ConsumptionType and RELATIVE stamina change amount.
+     * @return true if you want to cancel this update, otherwise false.
+     */
+    Consumption onBeforeUpdateStamina(String reason, Consumption consumption);
+}
\ No newline at end of file

src/main/java/emu/grasscutter/game/managers/StaminaManager/ConsumptionType.java

@@ -10,10 +10,10 @@ public enum ConsumptionType {
     SPRINT(-1800),
     DASH(-360),
     FLY(-60),
-    SWIM_DASH_START(-200),
-    SWIM_DASH(-200),
-    SWIMMING(-80),
-    FIGHT(0),
+    SWIM_DASH_START(-20),
+    SWIM_DASH(-204),
+    SWIMMING(-80), // TODO: Slow swimming is handled per movement, not per second. Movement frequency depends on gender/age/height.
+    FIGHT(0), // See StaminaManager.getFightConsumption()
 
     // restore
     STANDBY(500),

src/main/java/emu/grasscutter/game/managers/StaminaManager/README.md

+# Stamina Manager
+
+---
+## UpdateStamina
+```java
+// will use consumption.consumptionType as reason
+public int updateStaminaRelative(GameSession session, Consumption consumption);
+```
+```java
+public int updateStaminaAbsolute(GameSession session, String reason, int newStamina)
+```
+
+---
+## Pause and Resume
+```java
+public void startSustainedStaminaHandler()
+```
+```java
+public void stopSustainedStaminaHandler()
+```
+
+
+---
+## Stamina change listeners and intercepting
+### BeforeUpdateStaminaListener
+```java
+
+import emu.grasscutter.game.managers.StaminaManager.BeforeUpdateStaminaListener;
+
+// Listener sample: plugin disable CLIMB_JUMP stamina cost.
+private class MyClass implements BeforeUpdateStaminaListener {
+    // Make your class implement the listener, and pass in your class as a listener.
+
+    public MyClass() {
+        getStaminaManager().registerBeforeUpdateStaminaListener("myClass", this);
+    }
+
+    @Override
+    public boolean onBeforeUpdateStamina(String reason, int newStamina) {
+        // do not intercept this update
+        return false;
+    }
+
+    @Override
+    public boolean onBeforeUpdateStamina(String reason, Consumption consumption) {
+        // Try to intercept if this update is CLIMB_JUMP
+        if (consumption.consumptionType == ConsumptionType.CLIMB_JUMP) {
+            return true;
+        }
+        // If it is not CLIMB_JUMP, do not intercept.
+        return false;
+    }
+}
+```
+### AfterUpdateStaminaListener
+```java
+
+import emu.grasscutter.game.managers.StaminaManager.AfterUpdateStaminaListener;
+
+// Listener sample: plugin listens for changes already made.
+private class MyClass implements AfterUpdateStaminaListener {
+    // Make your class implement the listener, and pass in your class as a listener.
+
+    public MyClass() {
+        registerAfterUpdateStaminaListener("myClass", this);
+    }
+
+    @Override
+    public void onAfterUpdateStamina(String reason, int newStamina) {
+        // ...
+    }
+}
+```
\ No newline at end of file

src/main/java/emu/grasscutter/game/managers/StaminaManager/StaminaManager.java

@@ -33,13 +33,9 @@ public class StaminaManager {
     private GameSession cachedSession = null;
     private GameEntity cachedEntity = null;
     private int staminaRecoverDelay = 0;
-    private boolean isInSkillMove = false;
-    public boolean getIsInSkillMove() {
-        return isInSkillMove;
-    }
-    public void setIsInSkillMove(boolean b) {
-        isInSkillMove = b;
-    }
+
+    private HashMap<String, BeforeUpdateStaminaListener> beforeUpdateStaminaListeners = new HashMap<>();
+    private HashMap<String, AfterUpdateStaminaListener> afterUpdateStaminaListeners = new HashMap<>();
 
     public StaminaManager(Player player) {
         this.player = player;
@@ -91,36 +87,116 @@ public class StaminaManager {
         MotionStatesCategorized.put("FIGHT", new HashSet<>(Arrays.asList(
                 MotionState.MOTION_FIGHT
         )));
+
+        MotionStatesCategorized.put("SKIFF", new HashSet<>(Arrays.asList(
+                MotionState.MOTION_SKIFF_BOARDING,
+                MotionState.MOTION_SKIFF_NORMAL,
+                MotionState.MOTION_SKIFF_DASH,
+                MotionState.MOTION_SKIFF_POWERED_DASH
+        )));
+    }
+
+    // Listeners
+
+    public boolean registerBeforeUpdateStaminaListener(String listenerName, BeforeUpdateStaminaListener listener) {
+        if (beforeUpdateStaminaListeners.containsKey(listenerName)) {
+            return false;
+        }
+        beforeUpdateStaminaListeners.put(listenerName, listener);
+        return true;
+    }
+
+    public boolean unregisterBeforeUpdateStaminaListener(String listenerName) {
+        if (!beforeUpdateStaminaListeners.containsKey(listenerName)) {
+            return false;
+        }
+        beforeUpdateStaminaListeners.remove(listenerName);
+        return true;
+    }
+
+    public boolean registerAfterUpdateStaminaListener(String listenerName, AfterUpdateStaminaListener listener) {
+        if (afterUpdateStaminaListeners.containsKey(listenerName)) {
+            return false;
+        }
+        afterUpdateStaminaListeners.put(listenerName, listener);
+        return true;
+    }
+
+    public boolean unregisterAfterUpdateStaminaListener(String listenerName) {
+        if (!afterUpdateStaminaListeners.containsKey(listenerName)) {
+            return false;
+        }
+        afterUpdateStaminaListeners.remove(listenerName);
+        return true;
     }
 
     private boolean isPlayerMoving() {
         float diffX = currentCoordinates.getX() - previousCoordinates.getX();
         float diffY = currentCoordinates.getY() - previousCoordinates.getY();
         float diffZ = currentCoordinates.getZ() - previousCoordinates.getZ();
-        Grasscutter.getLogger().debug("isPlayerMoving: " + previousCoordinates + ", " + currentCoordinates +
+        Grasscutter.getLogger().trace("isPlayerMoving: " + previousCoordinates + ", " + currentCoordinates +
                 ", " + diffX + ", " + diffY + ", " + diffZ);
         return Math.abs(diffX) > 0.3 || Math.abs(diffY) > 0.2 || Math.abs(diffZ) > 0.3;
     }
 
-    // Returns new stamina and sends PlayerPropNotify
-    public int updateStamina(GameSession session, Consumption consumption) {
+    public int updateStaminaRelative(GameSession session, Consumption consumption) {
         int currentStamina = player.getProperty(PlayerProperty.PROP_CUR_PERSIST_STAMINA);
         if (consumption.amount == 0) {
             return currentStamina;
         }
+        // notify will update
+        for (Map.Entry<String, BeforeUpdateStaminaListener> listener : beforeUpdateStaminaListeners.entrySet()) {
+            Consumption overriddenConsumption = listener.getValue().onBeforeUpdateStamina(consumption.consumptionType.toString(), consumption);
+            if ((overriddenConsumption.consumptionType != consumption.consumptionType) && (overriddenConsumption.amount != consumption.amount)) {
+                Grasscutter.getLogger().debug("[StaminaManager] Stamina update relative(" +
+                        consumption.consumptionType.toString() + ", " + consumption.amount + ") overridden to relative(" +
+                        consumption.consumptionType.toString() + ", " + consumption.amount + ") by: " + listener.getKey());
+                return currentStamina;
+            }
+        }
         int playerMaxStamina = player.getProperty(PlayerProperty.PROP_MAX_STAMINA);
-        Grasscutter.getLogger().debug(currentStamina + "/" + playerMaxStamina + "\t" + currentState + "\t" +
+        Grasscutter.getLogger().trace(currentStamina + "/" + playerMaxStamina + "\t" + currentState + "\t" +
                 (isPlayerMoving() ? "moving" : "      ") + "\t(" + consumption.consumptionType + "," +
                 consumption.amount + ")");
         int newStamina = currentStamina + consumption.amount;
         if (newStamina < 0) {
             newStamina = 0;
+        } else if (newStamina > playerMaxStamina) {
+            newStamina = playerMaxStamina;
+        }
+        return setStamina(session, consumption.consumptionType.toString(), newStamina);
     }
-        if (newStamina > playerMaxStamina) {
+
+    public int updateStaminaAbsolute(GameSession session, String reason, int newStamina) {
+        int currentStamina = player.getProperty(PlayerProperty.PROP_CUR_PERSIST_STAMINA);
+        // notify will update
+        for (Map.Entry<String, BeforeUpdateStaminaListener> listener : beforeUpdateStaminaListeners.entrySet()) {
+            int overriddenNewStamina = listener.getValue().onBeforeUpdateStamina(reason, newStamina);
+            if (overriddenNewStamina != newStamina) {
+                Grasscutter.getLogger().debug("[StaminaManager] Stamina update absolute(" +
+                        reason + ", " + newStamina + ") overridden to absolute(" +
+                        reason + ", " + newStamina + ") by: " + listener.getKey());
+                return currentStamina;
+            }
+        }
+        int playerMaxStamina = player.getProperty(PlayerProperty.PROP_MAX_STAMINA);
+        if (newStamina < 0) {
+            newStamina = 0;
+        } else if (newStamina > playerMaxStamina) {
             newStamina = playerMaxStamina;
         }
+        return setStamina(session, reason, newStamina);
+    }
+
+    // Returns new stamina and sends PlayerPropNotify
+    public int setStamina(GameSession session, String reason, int newStamina) {
+        // set stamina
         player.setProperty(PlayerProperty.PROP_CUR_PERSIST_STAMINA, newStamina);
         session.send(new PacketPlayerPropNotify(player, PlayerProperty.PROP_CUR_PERSIST_STAMINA));
+        // notify updated
+        for (Map.Entry<String, AfterUpdateStaminaListener> listener : afterUpdateStaminaListeners.entrySet()) {
+            listener.getValue().onAfterUpdateStamina(reason, newStamina);
+        }
         return newStamina;
     }
 
@@ -141,7 +217,7 @@ public class StaminaManager {
         if (!player.isPaused() && sustainedStaminaHandlerTimer == null) {
             sustainedStaminaHandlerTimer = new Timer();
             sustainedStaminaHandlerTimer.scheduleAtFixedRate(new SustainedStaminaHandler(), 0, 200);
-            // Grasscutter.getLogger().debug("[MovementManager] SustainedStaminaHandlerTimer started");
+            Grasscutter.getLogger().debug("[MovementManager] SustainedStaminaHandlerTimer started");
         }
     }
 
@@ -149,7 +225,7 @@ public class StaminaManager {
         if (sustainedStaminaHandlerTimer != null) {
             sustainedStaminaHandlerTimer.cancel();
             sustainedStaminaHandlerTimer = null;
-            // Grasscutter.getLogger().debug("[MovementManager] SustainedStaminaHandlerTimer stopped");
+            Grasscutter.getLogger().debug("[MovementManager] SustainedStaminaHandlerTimer stopped");
         }
     }
 
@@ -188,17 +264,17 @@ public class StaminaManager {
         switch (motionState) {
             case MOTION_DASH_BEFORE_SHAKE:
                 if (previousState != MotionState.MOTION_DASH_BEFORE_SHAKE) {
-                    updateStamina(session, new Consumption(ConsumptionType.SPRINT));
+                    updateStaminaRelative(session, new Consumption(ConsumptionType.SPRINT));
                 }
                 break;
             case MOTION_CLIMB_JUMP:
                 if (previousState != MotionState.MOTION_CLIMB_JUMP) {
-                    updateStamina(session, new Consumption(ConsumptionType.CLIMB_JUMP));
+                    updateStaminaRelative(session, new Consumption(ConsumptionType.CLIMB_JUMP));
                 }
                 break;
             case MOTION_SWIM_DASH:
                 if (previousState != MotionState.MOTION_SWIM_DASH) {
-                    updateStamina(session, new Consumption(ConsumptionType.SWIM_DASH_START));
+                    updateStaminaRelative(session, new Consumption(ConsumptionType.SWIM_DASH_START));
                 }
                 break;
         }
@@ -206,7 +282,7 @@ public class StaminaManager {
 
     private void handleImmediateStamina(GameSession session, EvtDoSkillSuccNotify notify) {
         Consumption consumption = getFightConsumption(notify.getSkillId());
-        updateStamina(session, consumption);
+        updateStaminaRelative(session, consumption);
     }
 
     private class SustainedStaminaHandler extends TimerTask {
@@ -216,10 +292,10 @@ public class StaminaManager {
                 int currentStamina = player.getProperty(PlayerProperty.PROP_CUR_PERSIST_STAMINA);
                 int maxStamina = player.getProperty(PlayerProperty.PROP_MAX_STAMINA);
                 if (moving || (currentStamina < maxStamina)) {
-                    Grasscutter.getLogger().debug("Player moving: " + moving + ", stamina full: " +
+                    Grasscutter.getLogger().trace("Player moving: " + moving + ", stamina full: " +
                             (currentStamina >= maxStamina) + ", recalculate stamina");
+
                     Consumption consumption = new Consumption(ConsumptionType.None);
-                    if (!isInSkillMove) {
                     if (MotionStatesCategorized.get("CLIMB").contains(currentState)) {
                         consumption = getClimbSustainedConsumption();
                     } else if (MotionStatesCategorized.get("SWIM").contains((currentState))) {
@@ -231,7 +307,15 @@ public class StaminaManager {
                     } else if (MotionStatesCategorized.get("STANDBY").contains(currentState)) {
                         consumption = getStandSustainedConsumption();
                     }
-                    }
+
+                    /*
+                        TODO: Reductions that apply to all motion types:
+                            Elemental Resonance
+                                Wind: -15%
+                            Skills
+                                Diona E: -10% while shield lasts
+                                Barbara E: -12% while lasts
+                    */
                     if (cachedSession != null) {
                         if (consumption.amount < 0) {
                             staminaRecoverDelay = 0;
@@ -241,12 +325,12 @@ public class StaminaManager {
                             if (staminaRecoverDelay < 10) {
                                 // For others recover after 2 seconds (10 ticks) - as official server does.
                                 staminaRecoverDelay++;
-                                consumption = new Consumption(ConsumptionType.None);
+                                consumption.amount = 0;
+                                Grasscutter.getLogger().trace("[StaminaManager] Delaying recovery: " + staminaRecoverDelay);
                             }
                         }
-                        updateStamina(cachedSession, consumption);
+                        updateStaminaRelative(cachedSession, consumption);
                     }
-                    handleDrowning();
                 }
             }
             previousState = currentState;
@@ -261,10 +345,9 @@ public class StaminaManager {
     private void handleDrowning() {
         int stamina = player.getProperty(PlayerProperty.PROP_CUR_PERSIST_STAMINA);
         if (stamina < 10) {
-            boolean isSwimming = MotionStatesCategorized.get("SWIM").contains(currentState);
-            Grasscutter.getLogger().debug(player.getProperty(PlayerProperty.PROP_CUR_PERSIST_STAMINA) + "/" +
-                    player.getProperty(PlayerProperty.PROP_MAX_STAMINA) + "\t" + currentState + "\t" + isSwimming);
-            if (isSwimming && currentState != MotionState.MOTION_SWIM_IDLE) {
+            Grasscutter.getLogger().trace(player.getProperty(PlayerProperty.PROP_CUR_PERSIST_STAMINA) + "/" +
+                    player.getProperty(PlayerProperty.PROP_MAX_STAMINA) + "\t" + currentState);
+            if (currentState != MotionState.MOTION_SWIM_IDLE) {
                 killAvatar(cachedSession, cachedEntity, PlayerDieType.PLAYER_DIE_DRAWN);
             }
         }
@@ -272,7 +355,33 @@ public class StaminaManager {
 
     // Consumption Calculators
 
+    // Stamina Consumption Reduction: https://genshin-impact.fandom.com/wiki/Stamina
+
     private Consumption getFightConsumption(int skillCasting) {
+        /* TODO:
+            Instead of handling here, consider call StaminaManager.updateStamina****() with a Consumption object with
+                type=FIGHT and a modified amount when handling attacks for more accurate attack start/end time and
+                other info. Handling it here could be very complicated.
+            Charged attack
+                Default:
+                    Polearm: (-2500)
+                    Claymore: (-4000 per second, -800 each tick)
+                    Catalyst: (-5000)
+                Talent:
+                    Ningguang: When Ningguang is in possession of Star Jades, her Charged Attack does not consume Stamina. (Catalyst * 0)
+                    Klee: When Jumpy Dumpty and Normal Attacks deal DMG, Klee has a 50% chance to obtain an Explosive Spark.
+                            This Explosive Spark is consumed by the next Charged Attack, which costs no Stamina. (Catalyst * 0)
+                Constellations:
+                    Hu Tao: While in a Paramita Papilio state activated by Guide to Afterlife, Hu Tao's Charge Attacks do not consume Stamina. (Polearm * 0)
+                Character Specific:
+                    Keqing: (-2500)
+                    Diluc: (Claymore * 0.5)
+            Talent Moving: (Those are skills too)
+                Ayaka: (-1000 initial) (-1500 per second) When the Cryo application at the end of Kamisato Art: Senho hits an opponent (+1000)
+                Mona: (-1000 initial) (-1500 per second)
+         */
+
+        // TODO: Currently only handling Ayaka and Mona's talent moving initial costs.
         Consumption consumption = new Consumption(ConsumptionType.None);
         HashMap<Integer, Integer> fightingCost = new HashMap<>() {{
             put(10013, -1000); // Kamisato Ayaka
@@ -292,10 +401,12 @@ public class StaminaManager {
                 consumption = new Consumption(ConsumptionType.CLIMB_START);
             }
         }
+        // TODO: Foods
         return consumption;
     }
 
     private Consumption getSwimSustainedConsumptions() {
+        handleDrowning();
         Consumption consumption = new Consumption(ConsumptionType.None);
         if (currentState == MotionState.MOTION_SWIM_MOVE) {
             consumption = new Consumption(ConsumptionType.SWIMMING);
@@ -310,6 +421,7 @@ public class StaminaManager {
         Consumption consumption = new Consumption(ConsumptionType.None);
         if (currentState == MotionState.MOTION_DASH) {
             consumption = new Consumption(ConsumptionType.DASH);
+            // TODO: Foods
         }
         if (currentState == MotionState.MOTION_RUN) {
             consumption = new Consumption(ConsumptionType.RUN);
@@ -321,7 +433,12 @@ public class StaminaManager {
     }
 
     private Consumption getFlySustainedConsumption() {
+        // POWERED_FLY, e.g. wind tunnel
+        if (currentState == MotionState.MOTION_POWERED_FLY) {
+            return new Consumption(ConsumptionType.POWERED_FLY);
+        }
         Consumption consumption = new Consumption(ConsumptionType.FLY);
+        // Talent
         HashMap<Integer, Float> glidingCostReduction = new HashMap<>() {{
             put(212301, 0.8f); // Amber
             put(222301, 0.8f); // Venti
@@ -330,15 +447,15 @@ public class StaminaManager {
         for (EntityAvatar entity : cachedSession.getPlayer().getTeamManager().getActiveTeam()) {
             for (int skillId : entity.getAvatar().getProudSkillList()) {
                 if (glidingCostReduction.containsKey(skillId)) {
-                    reduction = glidingCostReduction.get(skillId);
+                    float potentialLowerReduction = glidingCostReduction.get(skillId);
+                    if (potentialLowerReduction < reduction) {
+                        reduction = potentialLowerReduction;
                     }
                 }
             }
-        consumption.amount *= reduction;
-        // POWERED_FLY, e.g. wind tunnel
-        if (currentState == MotionState.MOTION_POWERED_FLY) {
-            consumption = new Consumption(ConsumptionType.POWERED_FLY);
         }
+        consumption.amount *= reduction;
+        // TODO: Foods
         return consumption;
     }
 

src/main/java/emu/grasscutter/server/packet/recv/HandlerCombatInvocationsNotify.java

@@ -49,22 +49,23 @@ public class HandlerCombatInvocationsNotify extends PacketHandler {
 
 						session.getPlayer().getStaminaManager().handleCombatInvocationsNotify(session, moveInfo, entity);
 
-						// TODO: handle MOTION_FIGHT landing
-						//  For plunge attacks, LAND_SPEED is always -30 and is not useful.
+						// TODO: handle MOTION_FIGHT landing which has a different damage factor
+						// 		Also, for plunge attacks, LAND_SPEED is always -30 and is not useful.
 						//  	May need the height when starting plunge attack.
 
+						// MOTION_LAND_SPEED and MOTION_FALL_ON_GROUND arrive in different packets.
+						// Cache land speed for later use.
+						if (motionState == MotionState.MOTION_LAND_SPEED) {
+							cachedLandingSpeed = motionInfo.getSpeed().getY();
+							cachedLandingTimeMillisecond = System.currentTimeMillis();
+							monitorLandingEvent = true;
+						}
 						if (monitorLandingEvent) {
  							if (motionState == MotionState.MOTION_FALL_ON_GROUND) {
 								monitorLandingEvent = false;
 								handleFallOnGround(session, entity, motionState);
 							}
 						}
-						if (motionState == MotionState.MOTION_LAND_SPEED) {
-							// MOTION_LAND_SPEED and MOTION_FALL_ON_GROUND arrive in different packet. Cache land speed for later use.
-							cachedLandingSpeed = motionInfo.getSpeed().getY();
-							cachedLandingTimeMillisecond = System.currentTimeMillis();
-							monitorLandingEvent = true;
-						}
 					}
 					break;
 				default:
@@ -84,33 +85,42 @@ public class HandlerCombatInvocationsNotify extends PacketHandler {
 	}
 
 	private void handleFallOnGround(GameSession session, GameEntity entity, MotionState motionState) {
-		// If not received immediately after MOTION_LAND_SPEED, discard this packet.
+		// People have reported that after plunge attack (client sends a FIGHT instead of FALL_ON_GROUND) they will die
+		// 		if they talk to an NPC (this is when the client sends a FALL_ON_GROUND) without jumping again.
+		// A dirty patch: if not received immediately after MOTION_LAND_SPEED, discard this packet.
+		// 200ms seems to be a reasonable delay.
 		int maxDelay = 200;
 		long actualDelay = System.currentTimeMillis() - cachedLandingTimeMillisecond;
-		Grasscutter.getLogger().debug("MOTION_FALL_ON_GROUND received after " + actualDelay + "/" + maxDelay + "ms." + (actualDelay > maxDelay ? " Discard" : ""));
+		Grasscutter.getLogger().trace("MOTION_FALL_ON_GROUND received after " + actualDelay + "/" + maxDelay + "ms." + (actualDelay > maxDelay ? " Discard" : ""));
 		if (actualDelay > maxDelay) {
 			return;
 		}
 		float currentHP = entity.getFightProperty(FightProperty.FIGHT_PROP_CUR_HP);
 		float maxHP = entity.getFightProperty(FightProperty.FIGHT_PROP_MAX_HP);
-		float damage = 0;
+		float damageFactor = 0;
 		if (cachedLandingSpeed < -23.5) {
-			damage = (float) (maxHP * 0.33);
+			damageFactor = 0.33f;
 		}
 		if (cachedLandingSpeed < -25) {
-			damage = (float) (maxHP * 0.5);
+			damageFactor = 0.5f;
 		}
 		if (cachedLandingSpeed < -26.5) {
-			damage = (float) (maxHP * 0.66);
+			damageFactor = 0.66f;
 		}
 		if (cachedLandingSpeed < -28) {
-			damage = (maxHP * 1);
+			damageFactor = 1f;
 		}
+		float damage = maxHP * damageFactor;
 		float newHP = currentHP - damage;
 		if (newHP < 0) {
 			newHP = 0;
 		}
-		Grasscutter.getLogger().debug(currentHP + "/" + maxHP + "\t" + "\tDamage: " + damage + "\tnewHP: " + newHP);
+		if (damageFactor > 0) {
+			Grasscutter.getLogger().debug(currentHP + "/" + maxHP + "\tLandingSpeed: " + cachedLandingSpeed +
+					"\tDamageFactor: " + damageFactor + "\tDamage: " + damage + "\tNewHP: " + newHP);
+		} else {
+			Grasscutter.getLogger().trace(currentHP + "/" + maxHP + "\tLandingSpeed: 0\tNo damage");
+		}
 		entity.setFightProperty(FightProperty.FIGHT_PROP_CUR_HP, newHP);
 		entity.getWorld().broadcastPacket(new PacketEntityFightPropUpdateNotify(entity, FightProperty.FIGHT_PROP_CUR_HP));
 		if (newHP == 0) {