I've tried a bunch to make Rogue Bot work, but can't seem to get any reasonable degree of success. Missile unwieldy, while Grenade is expensive. Robo-bomb is my current guess for worst skill in the game. It's not 'does nothing' bad; it's 'use it and die horribly' bad. Place it and you risk an enemy walking diagonally adjacent to it from offscreen, setting it off in your face and killing you even from full health. One game was particularly good because I found a Rune of Zot and several piles of throwing nets. It made me question why I was using the Bot in the first place. Grenade props this guy up in Easy, but how is it supposed to get anything done on Rogue difficulty?