MArcomage

On turn 70 Chemo used Vampire lord + Ice revenant, that should have triggered Ice revenant's bonus attack since Vampire lord spawns Vampires wich are undead.
But there was no bonus attack.
That's because V.L. it's not considered an undead support card (so there is actually no error) but I wonder if it should be.

well it states "or replacing" and Vampire lord "replaces" so it should...not sure in terms how much it is actually necessary for the gameplay

Well I think it shouldn't. The previous card should be the one, which can summon revenant, and Vampire Lord can't.

It seems there is "support" key word in the card description that can be easily overlloked.
And Vampire Lord summons one certain card, that happens to be Undead, so that card actually is not Undead support.

Well, Vampire Lord summons an Undead support card, so you can try a three-way combo Vampire Lord + Vampire + Ice Revenant :P

Requires only 62 gems :)

And Vampire is not summoning nor replacing so it would not work

True

Ah yes!