Depending on the rendition, there is an immense arsenal of weaponry he could use against you. He often has a cannon of some sort, and some renditions even transform into a tank or stationary gun. That alone could be incredibly devastating, and that is before you factor in that he is known as a mad-scientist of sorts, and has conducted a vast number of ethically-ambiguous experiments and has created things that even scare Megatron!
There is almost no limit to the ways he could kill you.
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