To be honest, I think it's the most impressive builder I've seen so far on Kongregate - if anyone has seen a better one, don't judge me, think this is a very subjective view.
And why the hell souldn't you pay some tip for a game that's proper made and gives you some fun? If you don't like to build, well, play the game! If you like to build, well, give a tip!
Long story short: Why are you all complaining about giving credit to a good game? Do you really think everything in life should be for free? Wouldn't you pay for a well designed car? Or a fine meal? Or mobile ring tones? Or whatever you like?
In my opinion it's great you can play the game for free, if you want more, give it a tip. If not, leave.
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