What does Counterstrike apply to?

[RobotDrZaius]

If I Block an attack and apply the Counterstrike debuff, the wiki says "The next incoming melee attack will do double damage". Having just unlocked Skirmisher, I can attest that this is not literally correct - a sling bullet can trigger the Counterstrike bonus damage. But what about skills that use Weapon Damage, like Ice Claw or Swallow from a Wyrmic? And what about multiple attacks in a turn, like Dissolve (also Wyrmic, can you tell I'm thinking about a build...) - does the double damage only apply to 1 of the 4 attacks, or all?

[Lokean]

It's checked in attackTargetWith, so the first individual strike with a weapon during a full melee action.If you smack them with a two-handed sword out of max level Swallow, you're hitting for 520% weapon damage, and things go squelch. If you are dual wielding and use Dissolve, the first of the eight attacks is a counterattack, and you barely notice the extra damage.

[RobotDrZaius]

Interesting! So what about Ice Claw? It also uses Weapon Damage, but affects a frontal cone. Would Counterstrike magnify the hit to an enemy standing right in front of me when using this talent? What about an archer standing 3 tiles away that I blocked a shot from?

And thanks for the info so far!

[Lokean]

Counterstrike works by applying a debuff to the target; it doesn't care where the target is when it gets hit. So yes, it works with Ice Claw (on any targets in the cone that have counterstrike on them). Or with Wing Buffet.

It works with archery projectiles too.