The snake gets waaaayyy to long in the later levels. I managed to get flawless in the first 14 levels, but 15 is downright impossible to ace. Also, the tail should be more responsive to small movements.
My strategy for every level - max mana, max time stop, spawn weak units (but have strength in numbers), wait until you have ~300 mana while deflecting enemy attacks, then rush and keep the enemy frozen forever. If anything big is in the way, navigate as many units as you can past it and attack the base (the numbers are for this - many, especially strong, slow units, will get stuck here). The only time this didn't work was against the epic yeti, who could have crushed me if i hadn't luckily caused it to turn back for whatever reason a few steps before my base.
Not so good. For easy badges: Just take the best spread weapon, as many as possible, as your whole tank and go around the edges of arena firing blindly into the middle. You won't ever get below 70 HP, even on the hardest levels. At the end, buy the exploding gun and snipe all enemies to death. Don't use bubbles, they are a waste of time.
For everyone complaining: You have to select the perk you want to use.
Great game, although the 2-hour-merit is overkill - I had finished everything, bought every weapon and upgrade after one hour. 5/5
Also, after redoing a level you should be able to redo your choice! I accidentally clicked on the evolution point once and now can't get all abilites and thus not all achievements... And I'm nor going to do it all again.
Also, all the bosses were very easy, especially the last one. All you have to do is jump when he is in front of you and keep pumping out bullets. I didn't even move one step and won without taking damage.
Also, having more space makes this even easier. Coupled with the fact that you can maximize efficiency by placing factories in the right way but the AI seemingly cannot, there is really no challenge at all.
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