Darius, Wukong, Singed, Tryndamere. Just search up a tier list on reddit (too lazy to do that for you) and ban out the champions in tier 1 which you dont like facing.
Depends a lot what your team plays. Usually if you aren't aiming too high, you should just ban those champs what you hate most. Since those are probably the champs what you don't know how to counter or further more to play against.
Anyways, few champs what are probably hard to play against: Rumble, Singed, Lee, Kha, Riven. That tier-list what Pluckin Penguin posted is great but sometimes even low tier champions can be pain in the *** if they are part of cleaver team comp or maybe some diamond-Vayne for example can 1v3 your team sometimes. Anyways, I'd say that pick those champs from that tier-list what you hate most to play against.
Anyways, few champs what are probably hard to play against: Rumble, Singed, Lee, Kha, Riven. That tier-list what Pluckin Penguin posted is great but sometimes even low tier champions can be pain in the *** if they are part of cleaver team comp or maybe some diamond-Vayne for example can 1v3 your team sometimes. Anyways, I'd say that pick those champs from that tier-list what you hate most to play against.
But, more directed at your question:
Riven
Jarvan IV
Orianna
Tryndamere
Kassadin
These are some decent to high mobility champions with lots of damage potential.