This game is purely amazing. It's got extremely clean movement (although some way to slow down on ledges would be nice), the storyline is simple yet effective, and the boss at the end is by far (IMO) the best part of the game. If you haven't beat story mode yet, I highly suggest you take a few hours and do it. It's totally worth it and it really does get fun at the end with high-power weapons and the final boss. Has to be one of the best games I've ever seen, 11/10!
I say we add purchasable caffeine, because most "minions" can last longer than this one.
Then again, we're talking about a game where you can use solar power underground. I probably shouldn't talk reality here.
Honestly, why does everybody make suggestions on Kongregate? Do you really think that the mods/admins seriously care about Kongregate? The only thing on here that they do is release their game. If you want to make a suggestion take it over to their forums. It's honestly gotten so annoying when you get more than half of the comments being suggestions..
I love the fact that you respawn extremely quickly after completing a level or after a death. TIP: On levels such as level 50, if you hold the space button (not long enough for it to jump you again) you can jump further than usual.