Hello! I hope someone can help with this one, because it keeps coming up.

The Unstoppable card lets an eliminated unit counter before it is eliminated.

Does this permit a counter vs. Riverwatch Riders, which have the Vigilant ability that says units cannot counter against them.

Which ability wins, the unit Vigilant ability or the Lore card? I might guess that a golden rule here would be that Lore cards override unit abilities in general, but I do wonder if this is the intent in this case.

Also, concerning Unstoppable, I assume that Blood Harvesters will roll at the strength they had before the attack? So a BH unit with 2 figures would roll +1 dice on their counter, and a unit with 1 figure would roll +2?

I don't think you can counter attack River Riders with Unstoppable. My reasoning is that the lore card lets you use an action that you normally couldn't because you are eliminated. However, that action is ineffective against River Riders.

How have you played it?

The Blood Harvesters question is really interesting. But I can't think of a rationale for using any number other than the one you started with.

I received a reply from FFG, and the official answer is that Vigilant trumps Unstoppable. There can be no counters against Riverwatch Riders.