And how would I add a function, which will make possible to make visible three diffrent types of islands with other fuctions (like island without water - you need to stay on it for 3 seconds)

Sorry for my English,

i need to make a game. Game has a table (6*4), in bottom left square is start and in top right square is finish. With your character you need to come frome start to finish by jumping to islands. This islands are changing. On table there is always 8 islands. When they are visible you can jump on them, if they are not visible you die and it is game-over. This 8 islands are visible for randome amounts of time (5-10 seconds). When one become invisible there on other place one become visible for randome amount of time.

I already made start and finish and table. My character move in four directions, i just need to add this.

Thanks for your help.