Seeing as how Noctis resists every single one of Magus' preferred combat spells and also his transmutation, he may be inclined to use his other abilities once he realizes they aren't working. That said, how skilled is this Noctis? And yeah, Magus' barrier is a threat like always.
Both duplicate and teleport,
Both use elemental spells,
Both integrate some melee into their fighting styles,
Both seem to resist their basic abilities
So it comes down to skill and how likely are they to use the things not resisted by the other.
For Magus skill, I'm just gonna copy and paste what I wrote in the Diamondkix thread (cuz lazy)
"Magus does incorporate CQC on his fighting style (he literally tried an iaidō strike against Lavos), and is pretty comparable to Frog and Crono in skill, both very accomplished swordsmen, particularly Frog who was regarded as the best swordsman in the entire kingdom (and in one of the endings, it shows them both fighting in melee, with an ambiguous ending on who won; and that's frog using a sword that's designed to counter Magus, while Magus was occupied with his ritual to summon Lavos)"
"The entire cast fought
this thing and "won". Yeah, that should say more than enough.
(Describing
the thing)And can see infinite timelines at once, and also summoned the powers and abilities of every boss across the game enhanced, including Magus himself, while on top summoning alternate timeline versions of itself whenever close to losing until they figured out his core."