Sawbot

Sawbots are close to spinners because they do have a spinning weapon.

But contrarly to spinners or drums that features bars/discs/tribars, a sawbot's weapon is just (as the name implies) a saw or circular weapon (single component) attached to a motor. Middleweight and heavyweights can have multiple saws.

Sawbots suck in Stock RA2, but they can be very efficient in DSL.

Ninja, BOT-204 (and their DSL counterparts) and Spinner from the West are sawbots, but Ripblade isn't one because it has teeth on a disc, and this in both DSL and Stock.

Sawbots do generally less damage than spinners and have generally weaker weapons, but they do continuous damage and their weapons can't be blocked. Also, if it loses one of it's saws, a sawbot won't wobble like a normal spinner would.

Sawbots aren't at their best when horizontal, unlike spinners. Sawbots are better mounted as a vertical weapon.