Tornado
Tornado was agreed to be one of the tougher Middleweights and only one of two HS in that weight class (the other being REVENGE). The main weapon is two sledgehammers on a spinning bar, plus two 20cm pole spikes, so that it does not get stuck on its top. The bot can be easily flipped and Mauler Dances easily, which is a frequent problem for it in battle. It also spins his weapon only when the enemy is close, which hampers its effectiveness and damage potential.
The DSL version of Tornado is a shell spinner called Tempest.
Tempest is one of the best AI MW's. His weak plastic armor doesn't matters a lot since it has that half sheet on it's bottom, and it is damaging and has tough weapons. However, the polycarbonate extenders and sheets aren't very good for self-righting and if your bot lands a powerful hit on it (or rip off a hammer), it will probably tumble all across the arena (but not as badly as Insane Berserker does).