Officially, most formats have no cap on deck size
It is a rare example of a single card that has multiple avenues of self synergy
Alloy Myr, Altar of the Pantheon, Bonders Ornament, Chromatic Lantern, Coalition Relic, Cultivators Caravan, Darksteel Citadel, Dragons Hoard, Elementalists Palette, Foreboding Statue, Fountain of Ichor, Honored Heirloom, Letter of Acceptance, Mana Geode, Manalith, Network Terminal, Opaline Unicorn, Phyrexian Lens, Replicating Ring, Scuttlemutt, Skyclave Relic, Spinning Wheel, The Celestus, and Vessel of Endless Rest all outclass Celestial Prism in this way
Like most Magic: The Gathering cards, the value of Noctis, Prince of Lucis depends on a few consistent factors: its rarity, the printing and finish (regular or foil), its physical condition, and the set it was printed in (Final Fantasy)
Alongside this low demand, theres also a fairly robust supply, thanks to a reprint in Double Masters 2022
The iconic Disney villain and her feathered companion look predictably grumpy, but the purple hues look awesome