Okay so actually, I crashed when I made this thread the first time, so let's just hope I don't crash again!
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So these are my suggestions for this game:
1. A mechanic weapon, sort of like a bomb, that builds robots, centry guns, etc. (Like the robots and centry guns you can activate for a small amount of CE,
in some dungeons.) Only that it's a bomb, that builds stuff. Rather that, than a fourth weapon, which would be quite ridiculous. I mean, all good things come in threes, right?
2. A third upgrade from the Sealed Sword. I imagined a blue/green-ish kind. Shock damage, maybe? (I also came up with this really bad name, and it was late, so I suppose that would be the reason it sounds like something a four year old could've come up with; "Thundering Chief", you may laugh now.)
3. Silver keys from the Prize Wheel. Very, very rare though.
4. A forum suggestion, actually. The abillity to upload your own avatar image to use on the forums?
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So I hope you guys read them, and were somehow, either inspired to maybe come up with your own suggestions, or pay attention to those I came up with. Oh I don't know. Anyway, later.
I made a thread called the Constructor Series which corresponds to your first point:
http://forums.spiralknights.com/en/node/30230