Final Fantasy XVI shifted the series’ combat from turn-based systems to action-combat systems. Regardless of the validity of the arguments for or against it, Eikons like Ifrit and Titan are here and not getting swapped out. As such, here’s a couple of pointers to keep in mind about them.
Thoroughly Read Through Each Upgrade’s Details
For clarity, Eikons have two different types of powers: Abilities and Feats. Abilities are special attacks, while Feats are Eikon-specific moves, both of which Clive uses in combat.
Everything in the Eikon Ability menu has a brief description pop up when you hover over it. However, if you hit the triangle button while hovering over it, you’ll see many more details to each power. These details include the specific combo feat you’ll achieve with it, what you get for upgrading the ability, and any additional info on how to use it.
Only Master an Eikon’s Ability for Expanded Choices
Each Eikon has two ability slots. Those two ability slots belong to that Eikon’s abilities (not counting the Phoenix, who shares with Ifrit). The loophole, however, is when you Master an ability. Then you can place it wherever you want.

On the right, if any of the Phoenix’s abilities were Mastered, they could go in the other two Eikon’s slots as well.
For any trophy hunters reading, this is how to get the “Never Coming Down” trophy for landing all of Garuda’s abilities before landing.
That said, Mastery stops there for abilities (Eikonic Feats, a separate thing, do continue to upgrade). If your playstyle revolves around committing to keeping abilities in their own Eikon, save your Ability Points (AP) for other things.
Eikonic Abilities and Feats Occasionally Stand Above Dodging
Clive needs his dodging to survive long-term throughout Valisthea. That, or he can use a handful of Eikonic Abilities instead. Throughout the game you’ll unlock some skills that either build off of dodging or can fully replace it.
Those who played the demo might remember Eikons Garuda and Titan’s skillsets. Garuda has an ability that does extra damage if used at the perfect timing. Titan’s Eikonic Feat, Titanic Block, blocks an enemy attack, and if timed correctly, lets Clive punch (yes, punch) back with a Titanic Counter.