So I’ve been chewing on a thought for about an hour or so, and I thought I’d bring it up to the community site!
Here’s a Background Story:
I’m a PC in a silly high-level game of Coffee vs Tea with @Vrenshrrg (ask him all about it!). I often play as The Herbal Tea Shepherd Bryce and his dog Shennong. The Shepherd is build to exploit the Defend Interrupt action. During one particularly riveting fight, I thought that it would be awesome if my character, who spends most of his major actions outside of his own turn, could stop a target from making a boon invocation!
What Do You Think?
Could we find a way to make a balanced feat that allows a character to Interrupt a boon? Nullify Bane as a Defend action?
This makes a lot of sense as a house rule but personally I wouldn’t tie it to the Defend action. It has to be an interrupt, of course, but narratively it’s extremely different from defending yourself or an ally from an attack. I would possibly allow it to benefit from Sentinel, but all of the other Defend feats seem like a poor fit.
I would suggest a 2 point feat, and you have to beat the invocation roll as well as the invoking character’s Resolve (rather than the target’s Resolve, which is usually the case).
In the event of automatic success from Boon Focus, it should be a contested roll with the target using using the advantage from Boon Focus.
Cost: 2 points
Prerequisites: The ability to inflict Nullify
You are keen at stopping opponents from getting the upper hand in battle.
You may use a interrupt action to inflict the Nullify bane after an enemy has rolled a successful boon invocation. For the purpose of this feat, in order to ward of the boon, your roll must beat the opponent’s boon invocation roll or the opponent’s Resolve score, whichever is higher.
The interrupt action granted by this feat can benefit from the effects of the Sentinel feat, and counts towards the extra number of actions that are granted by Sentinel.
If the opponent automatically succeeds on the boon invocation roll that is targeted by this interrupt action because of the Boon Focus feat, then the opponent must contest the roll with an invocation roll. They receive additional advantage on their roll based on their tier of Boon Focus as follows:
Tier I: 3 Advantage
Tier II: 4 Advantage
Tier III: 5 Advantage
You don’t think Defensive Reflexes would be appropriate for this?
I think Bane Focus makes more sense as your source of advantage, and it’s the only feat which gives (reliable) advantage to bane attacks for a reason; Defensive Reflexes allows you to get a lot of advantage for comparatively cheap, which is potentially problematic.
There’s also the thematic weirdness that I mentioned. You could quite easily be rolling with advantage 6 if you Nullify as an Interrupt but only advantage 3 if you do it on your turn as a Focus Action. Seems kind of weird to me.
I agree, Defensive Reflexes shouldn’t count into this since it’s mostly an offensive Action.
Maybe there could actually be two Tiers of this Feat, one similar to how you wrote it and one that makes the Nullify take effect right with the Roll rather than just after, menaning an instantaneous Boon like Heal and Teleport could be prevented from taking effect.