I'm not sure how much testing went into the tank designer, but it seems to me that you should probably at least have to connect guns to a bubble. The optimum tank seems to basically be the highest DPS guns you can afford, resized to the smallest size, on their own with no bubbles.
A lot of these combinations don't make a damned bit of sense, a lot of these 'elements' aren't very elemental, and a lot of combinations that make sense don't work and have to be done another way.
I think the general drawing would be improved if rather than a drag-pencil, it used something like a spline tool. The jerky, jagged tracks produced by my incompetent trackpad flailings don't make for great rollercoaster action.
I don't think upgrades would improve this. It's an excellent game, and some more missions would be fun. *Possibly* being able to select your powerups would be good, too, but I'm not sure on that one.
Well implemented, but not very well planned. The controls feel awkward - the arrow keys oversensitive, the jumping charge too picky. And I don't really get any feeling of achievement out of it when I finish a level or complete an objective.
I hate the way that there's no incentive for winning quickly - if you let your riders grab the banner you lose out on all the cash you would have gained by killing everyone with arrows.
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 "Pixed"){kind=icon}
 "Doodle God"){kind=icon}
 "Loved"){kind=icon}
 "Rollercoaster Creator"){kind=icon}
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 "Level Up!"){kind=icon}