On survival around the time i set my third mega tower everything starts to get laggy to the point of making it unplayable. Might have to do with performance on the area towers, as they are the main component.
i was going to rate 5 but then i started noticing how certain K.I.S.S. awards are impossible (level 2-3) unless you do an elevator or play around with how the guy moves, and the problem with it is that this is a game about building bridges, not a reflex game!
Then the commonly commented fact that you can't resize sections of bridge, while irritating could be overlooked, but after the above mentioned problem it drills into my psych like a jackhammer at 5 AM.
3/5
really addicting, but can get tedious at the end when you need to craft a million things for each upgrade. maybe if you could make so that it builds all dependencies by pressing the craft button if you have enough material, but it would be complicated.
Overall great game, anything i would say would repeat what others say.
But, there are 3 things that just didn't feel right:
1) the music in the cutscenes make me think i'm playing creeper world,
2) the controls felt a little bit sticky when moving the characters, and
3) it would be nice to have in the level select menu tooltips over the characters repeating the small info you get when unlocking them and some sort of monster manual to be able to recap.
Everything that isn't in that list can get my seal of approval (once i make it, that is).
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 "Into Space 2"){kind=icon}
 "Cargo Bridge 2"){kind=icon}
 "Glean"){kind=icon}
 "Flip'd"){kind=icon}
 "Monster Bark"){kind=icon}