A few Predators (Yautja) vs Bumblebee, Optimus Prime & Megatron (Transformers)
The Predators like the City Hunter, Wolf from Aliens vs Predator: Requiem & (and) Ultimate (Upgrade) one vs the few Cybertronians of the movies while they may have the plasma cannons (since you guys kept on overestimating them) and the self-destruct while the first round shall begin with the City Hunter Predator vs Bumblebee.
Please also read the respect threads for the Transformers:
[list]Bumblebee
Optimus Prime
Megatron
[/list]