Yes, but last time I checked, stag doesn’t instantly sleep all four of your monsters unless its Mr. X’s account.
A poison immune multiple times purifier seems a bit excessive to me due to poison being the less threatening out of the 3 (sleep and stun can lock the enemy team something poison can’t do)
But poison can sweep your whole team in a blink of an eye something stun and sleep cant do
Yeah they each work differently. Poison is still one of the fastest ways to clear through an enemy team and if it’s set up to do that you need something very fast and with enough impact to enter the field. For example, a high speed monster with purify (Centaureon being one of the best).
With sleep it’s more about breaking the lock, then you can get back into play before everything gets slept again. Stun is about giving turn to those monsters or, something you can do with sleep too, kill / pull them back. In practice stun also just gets passed with time in a less harsh way than sleep unless they’ve gone and stunned you like mad.
Yukihime is great, Wraithcaptain too. Dreamy entrance and sleep / single sleep revenge are generally very viable. OoO is a thing. But yeah there definitely aren’t “sleep teams” or lots of monsters around like you can see for the other archetypes.