Warlocks and Spellcraft

[ChudoJogurt]

A character is in a duel with a powerful Warlock. The character is level 7 while the warlock is few levels higher but he has an ace up his sleeve - a Third Eye Dampening ready to activate. They know that Warlock tends to use various Meta-Spell-Like Abilities on their Eldritch Blast, so they want to use the Third Eye if and only if the Warlock uses Maximize on their Blast.

Is there a way for them to distinguish when the warlock uses their Metamagic or no?

[KillianHawkeye]

Normally you can't really use Spellcraft to identify a spell-like ability, but Warlocks do need to use somatic components for their invocations so you theoretically should be able to do it. I don't think they literally say so anywhere though, so you may have to convince your DM.

[Biffoniacus_Furiou]

The Spellcraft skill itself has no built-in mechanics for identifying metamagic on spells. i.e. a Spellcraft check can tell you what spell is being cast, but it can't tell you whether that spell was modified by any type of metamagic feat.

Even then, I'm not sure if a Third Eye: Dampen would help against a maximized spell. It says it reduces the variable numeric effects to the minimum result possible, but for a maximized spell the numeric effect is no longer variable. It basically makes it so the maximum is also the minimum for that casting, and the third eye activation changes nothing.

[Psyren]

Pathfinder allows Knowledge checks to identify certain feats being used, via the "Recall Intrigues" (https://www.d20pfsrd.com/skills/knowledge/) check. This includes identifying metamagic being applied to spells, which uses an Arcana check. While this is specific to spells as written, extending it to SLAs should be fairly reasonable.