[Saber Cherry]

I used to use fully decked Slayers as thugs, but they just die, even with a Lifelong Protection.

Proof that Assassins are not thugs:

0) Assume Assassins are thugs.
1) Regen is GREAT on living thugs.
2) Regen is not useful very unless the unit can survive taking damage a few times during a round of combat.
3) Units with less than about ceil(2d6) HP cannot take damage even once without a considerable risk of death.
4) Assassins have less than ceil(2d6) HP.
5) Therefore, regen is not very useful on Assassins.
6) This contradicts the original assumption, 0.

I'd be interested in hearing how you use them, though. I have found that even Black Servants, starting with 18 HP, ethereality, high MR, life-drain, and various immunities STILL can't be effective thugs. Maybe my definition of thug is too severe?

Edit: I also liked to use Werewolves as thugs, due to integral regen and decent stats. They always died too. I've had some success with Jotun Herses, though, using a Fire, Nature, or Water bless.