Review Time
Passive - Rotation:
Fortress has 4 shields rotating around him which block projectiles. After a delay, he regains one of the lost shields. Fortress gains armor and magic resist for each shield he currently has.
This could be very unfun to play against as ranged, as it just blocks projectiles. So maybe do something such as intercepts projectiles dealing reduced damage to Fortress, make it so he can protect better without just being un-interactive or give the shields a health bar to how much damage they can absorb. The stat boost with more shields up, makes him a good vs burst with is a needed niche.
W - Decimation:
Fortress pushes one of his shields towards nearby enemies, stopping at the first enemy champion hit and knocking them up.
Simple ability on surface, but could add depth or clarity to it. So like does it consume one of his shields around him to cast the ability, or just phrased that way for theme. and personal preference it should just be a knock back and or a stun rather than a knock up, because slamming a shield on someone doesn't usually knock them airborne. other than that simple useful ability
W - Traction:
Fortress extends one of his shields out dealing damage in a cone. If the shield hits an enemy champion, it pulls them into Fortress.
Simple ability, but the pull just seems random.
E - Direction:
Fortress extends his shields out for a short time dealing damage to enemies they slam into and reversing their rotation. If Direction hits an enemy champion with 3 shields, they are stunned and Fortress heals some of his missing health.
The high skill cap ability with reverse rotations and more disengage in his kit, making him a useful support vs divers/assassins overall. The heal seems kind of random, Personal Pref would be increased armor and MR or % dmg reduction unless it can be explained in lore.
R - Circlation:
Fortress regains any missing shields and pushes them out. Rotation increases significantly as they pull all nearby enemies to Fortress. Enemies successfully pulled all the way are stunned.
R - Resurrection:
Fortress regains any missing shields and revives a nearby ally who has died, also granting them shields.
Looks like 2 options one and just didn't decide. The circulation one, a slow pull into a stun seems impossible to code TBH, but it could function in his kit, with more peel a common theme; the increased circulation seems like it would cause his shield to go down much faster though, so maybe make them remain during his ultimate.
The resurrection is just completely broken, it is not a salvageable concept to revive allies in combat; but moving or adding the shields to an ally could also work much like a pseudo shield almost. so if it just moved his shields and was on a low-medium CD could be rather useful for his kit, and make his abilities cast from the target with them on maybe.
Flow with changes in mind
A front liner that intercepts projectiles for his marksman, uses q when someone tries to engage on them, which can then be comboed into W (first one) for a stun. His e is for skilled player to send a shield back and block more faster, express skill,; but it feels on its own with the Q/W already. The Ult is just mess in the kit, I recommend making it a simple transfer/add shields to an ally allowing Q/E to be cast from them making it feel like everything can work together.
So it has a good concept, just needs some more clarity, a new ult, and minor changes to the abilities for improved flow and lore explanation.