Warp Shield

Swirling purple energy fills a 20-foot cube centered on a point you can see within range. When you cast the spell, and as a bonus action on your subsequent turns, you can designate the field's matrix to be one of the following two types:

• ​Protect: The energy stabilizes allies within the matrix. A creature within the cube has Resistance to all damage types. When a creature starts its turn within the cube, it gains temporary hit points equal to 1d6 plus your spellcasting ability modifier. These temporary hit points replace any other temporary hit points granted by this spell, and they vanish when the spell ends or when the creature leaves the cube.
• ​Expose: The energy destabilizes everything within the matrix. Creatures inside the cube cannot benefit from any Resistances they possess. When a creature starts its turn within the cube, it must make a Constitution saving throw, taking 3d6 Necrotic damage on a failed save, or half as much on a successful one.

The spell ends early if you lose concentration, dismiss it (no action required), or cast it again. A creature must be entirely within the cube's area for these effects to apply to it. The effects of multiple Warp Shield spells do not stack; only the most recently cast spell applies.