who are the heroes with the absolute minimum requirement capable of physically taking down the following Transformers one-on-one without the use of any exotic powers (energy projection, magnetism, etc.) or anything sneaky like trying to mess up the robots from the inside.
... class 40-50 characters could probably face normal types, with 90-100 tonners needed for'em big'uns. I guess Optimus and other figureheads could stand up to 70-90 tonners, while types like Ravage could be held off by 20s or so... maybe.
Drax the Legend, Captain of the Fist, The Starwalker, The Jade Slayer