Cursna

[Shirai]

Indeed, should have Echo Drops, Assuming you have magic, and Holy Waters on you, even if only in one of the "quick to access" storage areas.

I have half a box dedicated to food and meds.
I always carry at least 2 to 3 stacks of Holies, Echos and a Vile/+1, also in the case of Doom on a vital job as tank (in case of a single tank) everyone able to cast cursna should be casting, not just the healer.

And as you said:

It really doesn't, it's NEVER going to be 100% success rate.

Doom is Russian Roulette, I've had times where I landed Cursna first or second try 20 times in a row and times where the victim's lifeless body dropped to the floor with 3 mages chaincasting Cursna and the guy chugging Holies like an alcoholic at a wedding party.