It's this with better art and animations, more weapons, etc.
Well, the big difference is the weapons instead of just the hook gun in Pang. I like Pang too but the art style here is more up my alley and I love the sense of humor in it as well.
I haven't gotten far enough into it to know how it mixes things up in variety of how the levels work (some of the Pang levels are pretty wild).
Hoping to get into it more over the weekend and can give better impressions then. Right now I'd say it's very impressive.
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Played some more and I'd say there really is a bigger difference in the two games than it appears on the surface. Pang has much more of a puzzle aspect to it, having to time your shots just at the right time, dependence on various obstacles, different ball reactions, etc.
Bug Butcher is much more of a pure action game. And it's a blast. Wide variety of enemy types, having to rescue little guys and just pure hecticness. As such, the graphics and animation are more of a part of the game (balls in Pang are, well, balls).
Both are great games but as far as the mobile versions, I'd give the edge to Bug Butcher for just pure addictive and a little more mindless fun.