Mark IV

A trinket that rewards frequent spellcasting — every fourth spell you cast grants +2 Intelligence permanently. Since Intelligence scales spell power and mana, this snowballs over a long run: more INT means stronger spells, which makes casting four of them more impactful, which triggers another +2 INT. Keep count of your casts and prioritize getting to that fourth spell as quickly as possible.

The counter resets after each proc — so every four casts adds +2 INT permanently, then the count restarts. In a fight where you cast 12 spells, you'd gain +6 INT by the end. Over a full run with many fights, the accumulated INT gain from Mark IV can dwarf any static INT-boosting item. The Two of Spades (doubles cheap spell casts) effectively doubles your cast count toward the Mark IV threshold.

Best on Mage builds or any cat that casts multiple spells per turn. The Mark IV is strongest in long runs with many fights rather than short aggressive ones — the permanent INT gain accumulates over time. Pair it with Human Brain (+2 INT, Uncommon) for an initial INT boost that makes early casts hit harder while the Mark IV ramps up.