Garlean attacks aren't magic, so what are they?

[Zero-ELEC]

Keep in mind their usage of ceruleum through magitek (personal magitek armour and weapons) do replicate magical abilities. It's how Regula was able to "enkindle" a ceruleum tiger familiar (the spell name is literally "Enkindle"). He presumably summoned it in a similar way arcanists summon carbuncles or summoners their egi (Enkindle use to be an arcanist/summoner spell before the revamp). Zenos magic swords are also bathed in ceruleum while in his special golf club scabbard, which allows him to use their powers.

Basically magitek isn't just technology powered by magic, although it is that at times (mostly with machina) but also technology that imitates and performs magic.

[SannaR]

Well from Zenos's short story he definitely wasn't able to use magic pre-resonant as he needed to have a sliver of wind crystal in his palm inorder to do the technique his weapons teacher kept on whipping his butt with. Who knows what a post resonant, post primal mounting, body hopping ect opened up for him on the ability to manipulate aether.

[Cassar]

I know that in our first encounter with Zenos he was capable of doing moves such as Concentrativity, which certainly looks like magic to me, but he also had access to Thunderous Force, Tempestuous Force, etc. You're saying he used crystals for those? I still think he must've had some sort of magic power, possibly from the supposed body-enhanced procedures I meant in my previous post or, as Lilimo suggested, maybe it was Emet's doing.

Elidibus can use magic regardless of the body he's in, just the same as Emet-Selch. Remember that before Endwalker, Emet-Selch is always in a Garlean body, and that doesn't stop him from being the world's most powerful mage.

Oh yeah, I know about Elidibus being able to use magic regardless. What I meant is that our fight against Zenos in 4.5 was similar to our first encounter with him, which led me to believe that the magic Hien was referring to was the same that we witnessed in the first encounter.

I'll read Zenos' short story again to see if there's anything I missed.