Guild Wars 2

If I have Retaliation up and someone I have not damaged hits me with an attack, does that tag them for purposes of me getting credit if they die?

Good question. Assumption. Yes.

Also have to assume yes, as you can see the damage ticks on screen.

Flame blast (sigil), and retaliation to me seem to tag nothing at all.

Yes it does. I usually run the trait which applies Retaliation on Aegis removal. In WvW when I’m on siege duty and a solo enemy decides to rush me, they activate my Retaliation, hit themselves for a few ticks, then gets swarmed. When they die, I get a lovely loot bag and all I did was stand there.

My main is a mesmer and I will even get loot bags when an enemy dies from hitting my Retaliation-phantasms.