diff --git a/README.md b/README.md
index b25c4eb..81fc3ea 100644
--- a/README.md
+++ b/README.md
@@ -3,5 +3,6 @@
 ## TODO:
 
 - [ ] Menu audio
-- [ ] Tags, zOffset from constants
+- [x] Tags, zOffset from constants
 - [ ] Add global game state (?)
+- [x] Add inertia to the player
diff --git a/source/main.lua b/source/main.lua
index 9743d86..46cd186 100644
--- a/source/main.lua
+++ b/source/main.lua
@@ -19,7 +19,9 @@ ZIndex = {
     props = 3,
     fx = 6,
     ui = 10,
-    alert = 12
+    alert = 12,
+    ground = 100,
+    flash = 101
 }
 CollideGroups = {
     player = 1,
diff --git a/source/scenes/Game.lua b/source/scenes/Game.lua
index ffed0fe..d8ebdba 100644
--- a/source/scenes/Game.lua
+++ b/source/scenes/Game.lua
@@ -45,6 +45,8 @@ end
 function scene:start()
     scene.super.start(self)
 
+    playdate.ui.crankIndicator:draw() -- not sure why this is not working
+
     self.optionsMenu:addMenuItem("Main Menu", function() Noble.transition(Menu) end)
     Noble.showFPS = true
 end
@@ -52,22 +54,22 @@ end
 function scene:spawnBaleba()
     local balebaCount = #scene.balebas
     if balebaCount >= 6 then
+        scene.balebaSpawner:remove()
         return
     end
 
-    scene.balebas[balebaCount + 1] = Baleba(math.random(410, 900), math.random(10, 210), scene.player, true)
-
-    return scene.balebas[balebaCount + 1]
+    --scene.balebas[balebaCount + 1] = Baleba(math.random(410, 900), math.random(10, 210), scene.player, true)
 end
 
 function scene:enter()
     scene.super.enter(self)
 
+
     scene.player = Player(150, 100)
     scene.ground = Ground(0, 225, scene.player)
 
     scene.balebaSpawner.timerEndedCallback = function()
-        --scene.balebas[k] = scene:spawnBaleba()
+        scene:spawnBaleba()
     end
 
     for i = 1, 3 do
@@ -107,7 +109,11 @@ function scene:update()
 
         playdate.timer.performAfterDelay(4000, function()
             scene.resultShowed = true
-            c = notify("Nice", function()
+            local message = "You failed!"
+            if scene.player.targetDone then
+                message = "You did it!"
+            end
+            c = notify(message, function()
                 Noble.transition(Menu)
                 c:remove()
             end)
diff --git a/source/scripts/balebaSprite.lua b/source/scripts/balebaSprite.lua
index 7d85795..9faf00f 100644
--- a/source/scripts/balebaSprite.lua
+++ b/source/scripts/balebaSprite.lua
@@ -15,10 +15,15 @@ function Baleba:init(x, y, player, loop)
     self.animation:setState("run")
 
     -- Collision properties
-    self:setZIndex(11)
+    self:setZIndex(ZIndex.enemy)
     self:setCollideRect(3, 25, 40, 15)
     self:setTag(154)
     self:setSize(64, 64)
+    self:setGroups(CollideGroups.enemy)
+    self:setCollidesWithGroups(
+        {
+            CollideGroups.player
+        })
 
     -- Sprite properties
     self.standrate = randomFloat(0.3, 2)
diff --git a/source/scripts/bigBoomSprite.lua b/source/scripts/bigBoomSprite.lua
index e18a3d4..927634a 100644
--- a/source/scripts/bigBoomSprite.lua
+++ b/source/scripts/bigBoomSprite.lua
@@ -12,7 +12,7 @@ function BigBoom:init()
     self:playAnimation()
     self:setCenter(0, 0)
     self:setSize(playdate.display.getSize())
-    self:setZIndex(120)
+    self:setZIndex(ZIndex.flash)
 
     self:moveTo(0, 0)
 
diff --git a/source/scripts/dangerSprite.lua b/source/scripts/dangerSprite.lua
index 9721ed0..18d024c 100644
--- a/source/scripts/dangerSprite.lua
+++ b/source/scripts/dangerSprite.lua
@@ -12,7 +12,7 @@ function Danger:init(x, y, dangerousObject)
     self.animation:setState("run")
 
     -- Collision properties
-    self:setZIndex(11)
+    self:setZIndex(ZIndex.alert)
     self:setTag(7)
     self:setSize(64, 64)
 
diff --git a/source/scripts/groundSprite.lua b/source/scripts/groundSprite.lua
index 07f4749..07c5f02 100644
--- a/source/scripts/groundSprite.lua
+++ b/source/scripts/groundSprite.lua
@@ -5,9 +5,14 @@ function Ground:init(x, y, player)
     Ground.super.init(self, "assets/sprites/groundFin")
 
     -- Collision properties
-    self:setZIndex(100)
+    self:setZIndex(ZIndex.ground)
     self:setTag(3)
+    self:setGroups(CollideGroups.wall)
     self:setCollideRect(0, 28, 800, 10)
+    self:setCollidesWithGroups(
+        {
+            CollideGroups.player
+        })
     self:setSize(800, 32)
 
     -- Main properties
diff --git a/source/scripts/player.lua b/source/scripts/player.lua
index 9692ce0..9813966 100644
--- a/source/scripts/player.lua
+++ b/source/scripts/player.lua
@@ -5,7 +5,7 @@ function Player:init(x, y)
 	Player.super.init(self, "assets/sprites/player", true)
 
 	-- Animation properties
-	self.animation:addState("run", 1, 7)
+	self.animation:addState("run", 8, 14)
 	self.animation.run.frameDuration = 2
 	self.animation:addState("up", 1, 7)
 	self.animation.up.frameDuration = 6
@@ -22,17 +22,27 @@ function Player:init(x, y)
 	-- Collision properties
 	self:setSize(64, 64)
 	self:moveTo(x, y)
-	self:setZIndex(10)
-	self:setCollideRect(3, 19, 63, 33)
+	self:setZIndex(ZIndex.player)
+	self:setGroups(CollideGroups.player)
+	self:setCollidesWithGroups(
+		{
+			CollideGroups.enemy,
+			CollideGroups.wall
+		})
+	self:setCollideRect(3, 19, 60, 33)
 	self:setTag(1)
 
 	-- Physics properties
+	self.fallSpeed = 0.05
 	self.xVelocity = 0
-	self.yVelocity = 0
+	self.yVelocity = self.fallSpeed
 	self.maxXSpeed = 2
 	self.maxYSpeed = 5
-	self.fallSpeed = 0.05
-	self.maxFallSpeed = 0.4
+	self.acceleration = 0.05
+	self.friction = 0.95
+	self.yInertia = 0
+	self.maxFallSpeed = 0.7
+	self.frictionAccel = 0.3
 
 	-- Player State
 	self.touchingGround = false
@@ -41,8 +51,9 @@ function Player:init(x, y)
 	Player.dead = false
 	Player.bat = 10000
 	Player.dischargeRate = 1
-	self.cantDown = false
 	Player.moveRight = false
+	self.lastDirection = nil
+	self.targetDone = false
 end
 
 function Player:handleInput()
@@ -52,54 +63,53 @@ function Player:handleInput()
 
 	local crankChange, acceleratedChange = playdate.getCrankChange()
 
-	if playdate.buttonJustReleased(playdate.kButtonLeft) or playdate.buttonJustReleased(playdate.kButtonRight) then
-		self.cantDown = false
-	end
-
-	if playdate.buttonIsPressed(playdate.kButtonLeft) then
-		self:changeToRunState("left")
-		self:setRotation(10)
-		self.cantDown = true
+	-- X velocity
+	if not playdate.buttonIsPressed(playdate.kButtonLeft) and not playdate.buttonIsPressed(playdate.kButtonRight) then
+		self.xVelocity = self.xVelocity * self.friction
 		Player.moveRight = false
-	elseif playdate.buttonIsPressed(playdate.kButtonRight) then
-		self:changeToRunState("right")
-		self:setRotation(10)
-		self.cantDown = true
-		Player.moveRight = true
 	end
 
+	local isChangingDirection = false
+	if playdate.buttonIsPressed(playdate.kButtonLeft) then
+		if self.lastDirection == "right" then
+			isChangingDirection = true
+		end
+		self:changeToRunState("left")
+		self.lastDirection = "left"
+		self.xVelocity = self.xVelocity - self.acceleration
+	elseif playdate.buttonIsPressed(playdate.kButtonRight) then
+		if self.lastDirection == "left" then
+			isChangingDirection = true
+		end
+		self:changeToRunState("right")
+		Player.moveRight = true
+		self.lastDirection = "right"
+		self.xVelocity = self.xVelocity + self.acceleration
+	end
+
+	if isChangingDirection then
+		self.xVelocity = self.xVelocity * self.frictionAccel
+	end
+
+	-- Y velocity
 	if crankChange ~= 0 then
-		local force = 0.01
 		if crankChange > 0 then
 			self.animation:setState("up")
 		else
 			self.animation:setState("down")
-			force = 0.05
 		end
-		self.yVelocity = self.yVelocity - acceleratedChange * force
-	elseif self.cantDown == false then
-		self.cantDown = false
-		self:changeToDownState()
+		self.yInertia = self.yInertia - (acceleratedChange * 0.007)
 	else
-		self.yVelocity = self.fallSpeed
+		self.yInertia = self.yInertia * self.friction
+		self.animation:setState("down")
 	end
 end
 
-function Player:changeToDownState()
-	Player.moveRight = false
-	self.yVelocity = self.fallSpeed
-	self.xVelocity = 0
-	self.animation:setState("down")
-	self:setRotation(0)
-end
-
 function Player:changeToRunState(direction)
 	if direction == "left" then
-		self.xVelocity = -self.maxXSpeed
 		self.animation.direction = Noble.Animation.DIRECTION_LEFT
 		self.animation:setState("run")
 	elseif direction == "right" then
-		self.xVelocity = self.maxXSpeed
 		self.animation.direction = Noble.Animation.DIRECTION_RIGHT
 		self.animation:setState("run")
 	end
@@ -129,12 +139,13 @@ function Player:handleMovementAndCollisions()
 	end
 
 	local xVel = self.xVelocity
+	local yVel = self.yVelocity + self.yInertia + self.fallSpeed
 
 	if (self.x < 20 and xVel < 0) or (self.x > 380 and xVel > 0) then -- Screen bounds
 		xVel = 0
 	end
 
-	local _, _, collisions, length = self:checkCollisions(self.x + xVel, self.y + self.yVelocity)
+	local _, _, collisions, length = self:checkCollisions(self.x + xVel, self.y + yVel)
 
 	self.touchingGround = false
 	self.touchingCeiling = false
@@ -161,12 +172,13 @@ function Player:handleMovementAndCollisions()
 			self:boom()
 			return
 		elseif collisionTag == 154 then -- Baleba
-			-- self:boom(collisionObject)
+			self:boom(collisionObject)
 			return
 		elseif collisionTag == 2 then -- Tank
 			self:boom()
 			BigBoom()
 
+			self.targetDone = true
 			local particleC = ParticlePoly(collisionObject.x, collisionObject.y)
 			particleC:setThickness(5)
 			particleC:setAngular(-15, 15)
@@ -180,7 +192,8 @@ function Player:handleMovementAndCollisions()
 			return
 		end
 	end
-	self:moveTo(self.x + xVel, self.y + self.yVelocity)
+
+	self:moveTo(self.x + xVel, self.y + yVel)
 end
 
 function Player:handleDischarge(state)
@@ -190,7 +203,7 @@ function Player:handleDischarge(state)
 	if Player.bat <= 0 then
 		Player.bat = 0
 		self.fallSpeed = 2
-		self:changeToDownState()
+		self.animation:setState("down")
 		return
 	end
 
@@ -198,6 +211,10 @@ function Player:handleDischarge(state)
 		self.fallSpeed = self.maxFallSpeed
 	end
 
+	if Player.bat < 3000 then
+		self.frictionAccel = 0.4
+	end
+
 	if state == "run" then
 		Player.dischargeRate = 5
 	elseif state == "up" then
@@ -216,7 +233,6 @@ end
 function Player:update()
 	self:handleMovementAndCollisions()
 	if Player.dead then
-		print("Player is dead")
 		return
 	end
 
diff --git a/source/scripts/tankSprite.lua b/source/scripts/tankSprite.lua
index de51216..aa55aaa 100644
--- a/source/scripts/tankSprite.lua
+++ b/source/scripts/tankSprite.lua
@@ -16,9 +16,14 @@ function Tank:init(x, y, player, ground)
     Graphics.popContext()
 
     -- Collision properties
-    self:setZIndex(99)
+    self:setZIndex(ZIndex.enemy)
     self:setTag(2)
     self:setCollideRect(4, 56, 147, 65)
+    self:setGroups(CollideGroups.enemy)
+    self:setCollidesWithGroups(
+        {
+            CollideGroups.player
+        })
 
     -- Main properties
     Tank.moveSpeed = 2