I liked to use him on Classic Warlock, since you start at 38 Health.
The thing with Sardo though, is to not even worry about trying to offset the life loss, when he hits the table you should be planning to either end the game before it matters, or dump him off on the Altar for +8 melee/pierce and THEN end the game. When you have commited to casting him, all efforts are now either supporting Sardonyx (Nullifies, Commands, etc), fighting along side him, offering ranged support damage, or clearing a path for him (purging debuffs, purging opposing buffs, getting rid of obstacles), Or just spamming Jinxes on the opponent... trying to offset the life loss is mana and actions spent to prolong things that need to rather be invested to ending the game faster.
As long as Sardo is causing more than 2 damage every round, the opponent is on the same clock you are. If you land multiple successful zone wide Rots, he is dealing way more damage to the opponents forces than he is costing you.
I have found there are 2 big threats if you are using him:
Agony- You have to keep this off of him. Agony makes his main attack 3 dice, and his ranged attack 1. If the opponent has Aegis, Voltaric Sheild or respectable Armor, Agony makes his damage almost ignorable. Remember.. he has to be landing more damage every turn than he is inflicting.
Light Attacks- +2 vs Non-living sucks when you dont have armor. Whats worse though is that +2 on effect rolls for stun/daze. As mentioned, Sardo MUST be doing damage because he sets a clock. Any round that he does 0 Damage from a failed Daze check or a missed turn do to Stun is a round that Sardo hurt you more than the opponent. Temple of Light can put him on absolute lockdown. Daze/Stun damage barriers like the Lightning one, or the Circle of Light promo slow him down bad too.. though he is likely to just start spamming his ranged Rot chances at that point.
