Veranthos, the Theorem Lens
Veranthos was first ground and inscribed by a theorist-mage who believed all magical resistance was simply a misalignment of frequencies — a problem of geometry, not power. She spent thirty years etching axioms into its crystalline face, each one a proof that the universe's rules were merely suggestions to those who understood them deeply enough. The lens passed from scholar to scholar after her death, each new owner finding that it whispered faintly when brought near a powerful ward, as if cataloguing weaknesses for future study.
Mechanics
A crystalline lens arcane focus that unravels spell resistance and lets the wielder reshape spell geometry on the fly.
Theorem Engine
Veranthos, the Theorem Lens holds 5 charges and regains 1d4+1 expended charges daily at dawn. While using this item as your spellcasting focus, all activated abilities below draw from this pool.
Refraction Hex
When you cast a spell that requires a spell attack roll or forces a saving throw, you may expend 1 charge as part of casting the spell. Until the end of this turn, treat the target's resistance to the spell's damage type as if it were only normal damage (not doubled reduction), and treat the target's immunity as if it were only resistance. This does not strip conditions or other non-damage effects of the immunity.
Lens Shift
When you cast a spell with an area of effect (cone, cube, cylinder, line, or sphere), you may expend 2 charges as part of casting it to rotate or reposition the area's point of origin up to 15 feet in any direction from where it would normally originate, provided the new origin is within the spell's normal range and remains within your line of sight. The spell's range, area size, and all other parameters are otherwise unchanged.
Postulate Shield
As a reaction, when you fail a Constitution saving throw to maintain concentration on a spell, you may expend 2 charges to succeed instead. You may declare this reaction after seeing the result of the saving throw but before the DM resolves the concentration break.
5 charges
Recharges 1d4+1 at dawn
DM Notes
Balance considerations: Refraction Hex is the most impactful ability — stripping immunity down to resistance can meaningfully alter encounters against creatures like fire elementals or undead. DMs should be aware that at levels 5–7, most immunities are intentional encounter design choices; allow this effect freely but consider whether any single encounter hinges entirely on an immunity as its difficulty anchor. If so, Refraction Hex will shift that encounter's feel noticeably. Postulate Shield is strong but costs 2 charges and requires a failed save, making it a meaningful resource decision rather than a freebie — it rewards players who track their concentration carefully. Lens Shift adds positioning utility that can shortcut certain terrain puzzles or let AoE spells reach enemies behind cover; this is largely a player-skill reward and should not need restriction. With only 5 charges and variable recharge (average 3.5 regained), players will feel real scarcity across a full adventuring day. Suggested introduction: found in the estate of a dead arcanist, still tucked inside a case of geometric diagrams.
Generated with: Level 5 · Arcane focus · Heroic · Rare