def move(): Unit = {

    grow()
    shrink()

    if (body.tail.contains(body.head)) game.enterGameOverState()

    game.entities.foreach{
      ent => if (ent.isOccupyingBlockAt(body.head)) {
        ent match {
          case c:CanTeleport => grow(); ent.reset()
          case _ =>
        }
      }
    }
    if (game.players.length > 1) {
      val other_snake = game.players.find(p => p.snake.headColor != headColor).get.snake

      if (isHeadCollision(other_snake)) {
        dir match {
          case North | South => dir = East; other_snake.dir = West
          case East | West => dir = North; other_snake.dir = South
          case _ =>
        }
      }

      if (isTailCollision(other_snake)) game.enterGameOverState()
  }

  } // väx och krymp enl. regler; action om äter frukt