right before the end of the game you should heal yourself, it will greatly increase your income if you got full health at the end of the level, if your health pack still empty just duck and wait for it to regenerate
the resurrect is stupid! why don't you just automatically detect if you don't have the resurrection thing instead of asking me the same question 10000 damn time
do you want to cheat? its easy, select the "replay level" button at the start by using W,A,S,D then just skip all the shitty, intoxicating puzzle with shit graphic, bye bye motion sickness.
can you please at least give us undo skill choice button? its annoying to use 2 golds and reset every character skill if you choose the wrong upgrade for 1 character