@seedking Disagree with the last point. I maxed out health as soon as I had the bronze trophy, and was able to get up to level 29, 1m score, 1k kills and several other max ability badges in a single game. Health is really useful late game, because a single large enemy can knock a big chunk of your health off. If regen is maxed, you can make up that chunk so long as you can avoid enemies for a few seconds.
I found Energetic Red hardest, until I realised that if you use your least powerful engine with the Hornet, you hardly get anywhere in 100 seconds, so you don't use up much energy/take much damage.
It's definitely worth changing the colours of two characters when you can. What you lose in spread, you more than make up for in terms of being able to have all five characters fight each turn. I found that making the character with the best skill (the archer IMO) be on his own in terms of colour helped, because when characters share a colour they also share skill points.
The game is visually very nice. But I just have no idea why there are missions where I just watch AI characters fight one another with no input from me.
Got to say I disagree with a lot of the comments about the upgrading/switching system. Isn't the point that the tower is entirely mechanical, so stuff has to physically move around to work? It's more effort, but juggling all these various aspects is what differentiates the game.
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