I've been using vampire on multiple characters for a while now, and recently tried to give drain another shot, but I don't believe the heal is working as intended.
It's supposed to be a 3 second channel that restores 20% of my "missing" health every 1 second for 3 seconds.
You'd think that this would mean that using it at low health would heal me for large chunks even in PVP, but it actually seems to heal me for more when at higher health.
I can't confirm this with a combat log as I'm on xbox NA, so I'd like to check in with those that do to confirm this.
USA to New Zealand transplant.