Maybe wall more kind of mouse bigger screen verticaly.Some time before the level for placing stuff.Poison cheese explosion gun.Music ok but sound effect can be better.
Some boss armor regeneration too high.The hangling poor.Bullet speed too slow.Need more large non boss core. Can't run or hide ennemie and boss follow everywhere.The game good but need improvement.
Well just a code when you go on specific spot turn on. Need reach the exit when all checkpoint are on.I not a games developer so not sure if can be done on flash games but i think this shouldn't be hard.Maybe i should learn some basic but where.