diff --git a/sonic-radiance.love/scenes/battlesystem/actors/hero.lua b/sonic-radiance.love/scenes/battlesystem/actors/hero.lua
index ac8cd14..0d0148c 100644
--- a/sonic-radiance.love/scenes/battlesystem/actors/hero.lua
+++ b/sonic-radiance.love/scenes/battlesystem/actors/hero.lua
@@ -69,6 +69,13 @@ function Hero:getNewAnimation(animation)
   end
 end
 
+function Hero:flee()
+  if (not self.isKo) then
+    self:changeAnimation("walk")
+    self:goTo(-80, self.y, 3)
+  end
+end
+
 -- DRAW FUNCTIONS
 -- Draw everything related to the hero
 
diff --git a/sonic-radiance.love/scenes/battlesystem/controllers/ennemy.lua b/sonic-radiance.love/scenes/battlesystem/controllers/ennemy.lua
index d9a2652..b8e5e01 100644
--- a/sonic-radiance.love/scenes/battlesystem/controllers/ennemy.lua
+++ b/sonic-radiance.love/scenes/battlesystem/controllers/ennemy.lua
@@ -29,11 +29,22 @@ function EnnemyController:addVillain(ennData)
   end
 end
 
+function EnnemyController:getHighestSpeed()
+  local highestSpeed = 0
+  for i, villain in ipairs(self.list) do
+    if (villain.abstract.stats.speed > highestSpeed) then
+      highestSpeed = villain.abstract.stats.speed
+    end
+  end
+  return highestSpeed
+end
+
 function EnnemyController:addBoss(ennData)
   local boss = Villain(self, ennData.category, ennData.name, self:count() + 1)
   boss:setBonus(ennData.pvFactor, ennData.statFactor)
   boss.isBoss = true
   boss:setCheapEffect(ennData.cheapEffect)
+  self.owner.canFleeBattle = false
   self:add(boss)
 end
 
diff --git a/sonic-radiance.love/scenes/battlesystem/controllers/fighters/systems/actions/flee.lua b/sonic-radiance.love/scenes/battlesystem/controllers/fighters/systems/actions/flee.lua
index def62b6..0e0a949 100644
--- a/sonic-radiance.love/scenes/battlesystem/controllers/fighters/systems/actions/flee.lua
+++ b/sonic-radiance.love/scenes/battlesystem/controllers/fighters/systems/actions/flee.lua
@@ -11,7 +11,21 @@ end
 
 function FleeAction:startAction()
   core.debug:print("cbs/action", "Starting flee action")
-  self:finishAction()
+  if (self.fighter.abstract.name == "shadow") then
+    self.fighter.turns.hud:showMessage("You won't flee the battle")
+    self:finishAction()
+    return
+  end
+
+  local chanceToFlee = self.fighter.turnSystem:getChanceTooFlee(self.fighter.abstract.stats.speed)
+  if (math.random(100) < chanceToFlee) then
+    self.fighter.turnSystem.hud:showMessage("You flee the battle")
+    self.fighter.turnSystem:fleeBattle()
+  else
+    self.fighter.turnSystem.hud:showMessage("You failed to flee the battle")
+    self:finishAction()
+  end
+
 end
 
 return FleeAction
diff --git a/sonic-radiance.love/scenes/battlesystem/controllers/init.lua b/sonic-radiance.love/scenes/battlesystem/controllers/init.lua
index 4d96f2e..91490a4 100644
--- a/sonic-radiance.love/scenes/battlesystem/controllers/init.lua
+++ b/sonic-radiance.love/scenes/battlesystem/controllers/init.lua
@@ -24,6 +24,8 @@ function TurnController:new(scene, battleData)
 
   self.currentFighter = nil
 
+  self.canFleeBattle = true
+
   self.hud = HUD(self)
 
   self.player = Player(self)
@@ -34,6 +36,18 @@ function TurnController:new(scene, battleData)
   self:applyDeath()
 end
 
+function TurnController:getChanceTooFlee(value)
+  if (self.canFleeBattle) then
+    local speedComparison = math.min(value / self.ennemies:getHighestSpeed(), 1.5)
+    return 25 + (50 * speedComparison)
+  end
+end
+
+function TurnController:fleeBattle()
+  self.player:fleeBattle()
+  self.scene:fleeBattle()
+end
+
 function TurnController:showMessage(message)
   self.hud:showMessage(message)
 end
diff --git a/sonic-radiance.love/scenes/battlesystem/controllers/player.lua b/sonic-radiance.love/scenes/battlesystem/controllers/player.lua
index 007e734..cf9d54f 100644
--- a/sonic-radiance.love/scenes/battlesystem/controllers/player.lua
+++ b/sonic-radiance.love/scenes/battlesystem/controllers/player.lua
@@ -14,6 +14,13 @@ function HeroFighterController:initHeroes()
   end
 end
 
+
+function HeroFighterController:fleeBattle()
+  for i, hero in ipairs(self.list) do
+    hero.actor:flee()
+  end
+end
+
 function HeroFighterController:draw()
   for i, hero in ipairs(self.list) do
     hero:drawHUD()
diff --git a/sonic-radiance.love/scenes/battlesystem/gui/hud.lua b/sonic-radiance.love/scenes/battlesystem/gui/hud.lua
index fd4b856..47e9127 100644
--- a/sonic-radiance.love/scenes/battlesystem/gui/hud.lua
+++ b/sonic-radiance.love/scenes/battlesystem/gui/hud.lua
@@ -26,7 +26,6 @@ end
 function HUD:showMessage(message)
   self.message = message
   self.messageOpacity = 1
-  self.tweens:resetTweens()
   self.tweens:newTween(0, 0.2, {messageOpacity = 1}, 'inOutCubic')
   self.tweens:newTween(1, 0.2, {messageOpacity = 0}, 'inOutCubic')
 end
diff --git a/sonic-radiance.love/scenes/battlesystem/init.lua b/sonic-radiance.love/scenes/battlesystem/init.lua
index 2fa39e3..2fe636d 100644
--- a/sonic-radiance.love/scenes/battlesystem/init.lua
+++ b/sonic-radiance.love/scenes/battlesystem/init.lua
@@ -9,6 +9,8 @@ local Turns         = require "scenes.battlesystem.controllers"
 local VictoryScreen = require "scenes.battlesystem.screens.victory"
 local GameOverScreen = require "scenes.battlesystem.screens.gameover"
 
+local TweenManager = require "game.modules.tweenmanager"
+
 function BattleSystem:new(battleData)
   BattleSystem.super.new(self)
 
@@ -23,6 +25,7 @@ function BattleSystem:new(battleData)
   self:startBattle()
 
   self.screen = nil
+  self.tweens = TweenManager(self)
 end
 
 function BattleSystem:playMusic(music)
@@ -47,6 +50,17 @@ function BattleSystem:finishBattle()
   self.screen = VictoryScreen(self)
 end
 
+function BattleSystem:fleeBattle()
+  self.tweens:newTimer(2, "flee")
+end
+
+function BattleSystem:timerResponse(name)
+  if (name == "flee") then
+    --placeholder, pour l'instant on retourne juste au menu
+    scenes.debug.menu()
+  end
+end
+
 function BattleSystem:looseBattle()
   self.screen = GameOverScreen(self)
 end
@@ -59,6 +73,7 @@ function BattleSystem:haveMenus()
 end
 
 function BattleSystem:update(dt)
+  self.tweens:update(dt)
   self.world:update(dt)
   self.turns:update(dt)
   if (self.screen ~= nil) then