There are providers that focus more on volatility but I think you can find some very hard hitting games from each one. Here is a little list

Nolimit: Folsom prison, Mental, San quentin
Hacksaw: Gladiator legends, Wanted

Yggdrasil, Zeppelin, multifly, vampires riches

Pragmatic: Zeus vs hades, Gates of olympus, barn festival

Netent: Dead or alive 1 and 2

Relax gaming: Beast mode

Push gaming: Razor returns

Just some you can maybe give a try.