survival game

Erm.. have you tried dropping the grenades by pressing space? If they explode on top of the aliens, they should die. TY very much, any ideas for improvement? :)

Is there a time limit on this game? If so, you should probably mention it in the description or instructions. If not, what causes the player to die after like 20 seconds?

yup, sometimes you die randomly, im not sure, but you may take a look in the files and see if you can find the error :) Source: http://www.greenfoot.org/scenarios/5102