Primordial Fracture
Traits
Legendary Resistance (3/Day).
Unstable Elements. At the start of its turn, the Primordial Fracture takes on an elemental form, at random (or by choice): Fire, Water, Earth, Air. The form determines the following:
| Form | Immunity | Aura (10 ft., DC 19 CON save, 14 (4d6) on a failure) |
|---|---|---|
| Fire | Fire | Fire damage |
| Water | Cold | Cold damage + Speed reduced by 10 ft. |
| Earth | — (Resistance: all physical) | Bludgeoning damage + Prone |
| Air | Lightning | Lightning damage + pushed 10 ft. |
Elemental Body. Can pass through a 1-inch gap without squeezing.
Actions
Multiattack. Makes three Elemental Strike attacks.
Elemental Strike. Melee Attack Roll: +10, reach 15 ft. Hit: 18 (3d8 + 5) damage — damage type varies with its current form (Fire / Cold / Bludgeoning / Lightning).
Planar Rift (Recharge 5–6). The Primordial Fracture tears open a rift between planes. A 20-foot-radius Sphere within 60 feet. Every creature in that area makes a DC 19 Constitution save.
- Failure: 45 (10d8) Force damage, and the target is banished to a random elemental plane for 1 turn — it has the Incapacitated condition and does not exist on the Material Plane. It reappears Prone at the end of its next turn.
- Success: Half damage.
Legendary Actions (3/Round)
Shift Form. Instantly changes its Unstable Elements form.
Elemental Strike (Costs 2). Makes one attack.
How to Use
A different enemy every turn. The party can't rely on a single Resistance — if you have Fire Resistance, it shifts to its Water form.
Legendary Action: Shift Form is the cruelest part: the party says "okay, it's in Fire form now, let's cast Cone of Cold" — the Fracture instantly shifts to Water form and becomes immune to Cold.
Key
Force damage (immune to none of its forms) and Radiant/Necrotic/Psychic (none of the four forms cover these).