Only thing that really annoys me is when I can stack more gems, but the grab pieces area or whatever you wanna call it, gets in the way and you can't place them
I actually found the medium badge to be really easy... I'd show my maze, But I don't think I can put pictures on here, basically may a maze that zig zags a lot put all (except the swarm) towers in places where the creeps pass a lot, put 2 swarm towers in the middle, start with one, then once it's fully upgraded, you can build the second, but otherwise, build 1 squirt, fully upgrade, get a second, do the same, then a frost, and upgrade, then just put squirt in other places that the enemies pass a lot. It'd be a lot easier to explain with pictures.. ):
If you have a weapon that reloads one shot at a time (Such as a shotgun or rifle), instead of using the whole clip and reloading, reload imediately after each shot, you shoot barel (if any) slower, and you never have a long gap of not shooting
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