Psychomachia vs Unleash Hell's Fury

I'm not entirely sure how Psychomachia on and vs. Unleash Hell's Fury is resolved.

The block is successful, which should trigger the Unleash Hell's Fury. But, on the other hand, the block failed, which would mean that the block was not successful.

If the Unleash Hell's Fury is triggered, is the damage dealt immediately, before the chance to resolve "the block fails" of Psychomachia?

Or "the block fails" negates the block (similar to Elder Impersonation)?

Or if the Unleash Hell's Fury is triggered, but the damage is delayed until after the action (which sounds weird, but I want to be sure)?


Psychomachia
Only usable when an ally or younger vampire successfully blocks before locking the blocker.
Cancel the current action and unlock this acting vampire. The blocking minion is not locked.
The block fails, and the action continues. The blocking minion cannot attempt to block this action again.
As above, and the blocking minion takes 1 damage (damage not preventable).

Unleash Hell's Fury
+1 stealth action. Requires an infernal vampire. Unique.
Put this card in play. This card can attempt to block a Ⓓ action against you (or a card you control) and is considered a 9-capacity infernal vampire with +2 intercept during that attempt; if successful, the acting minion takes 1 unpreventable environmental aggravated damage and this card is burned.
As above, and unlock this vampire.

Palamedes wrote:

I'm not entirely sure how Psychomachia on and vs. Unleash Hell's Fury is resolved.

When the block is successful the effect of Unleash Hell's Fury is triggered and has to be handled before any other effect can be played because it is a delayed effect which has priority i.e. Psychomachia cannot be played before handling the 1 unpreventable environmental aggravated damage from Unleash Hell's Fury effect which probably leads to the end of the action as the acting vampire would no longer be ready.

Palamedes wrote:

Or "the block fails" negates the block (similar to Elder Impersonation)?

The difference is that elder impersonation (and other cards I cant remember) is played when "minion attempts to block". This means the block is never successful and unleash doesn't trigger.

Psychomachia would be played after block is successful so unleash does trigger and needs to be handled as inm8 said.