Second Skin - Tree Blight

You have been gifted a Second Skin. When you transform, you touch the green redwood broach and cast alter self, turning you into a Tree Blight 2 times per long rest. You take on the size and actions of the creature stats when in your second skin, but retain your character stats and can spell cast in this form.

You involuntarily transform when you hear bells ringing.

Transformation. You can cast the Alter Self spell to appear in your second form. When you do so, you gain the effects of that spell’s Change Appearance option and cannot end it to gain the benefits of a different option. Casting Alter Self in this way requires no spell slot. Your spellcasting ability for this spell is Intelligence, Wisdom, or Charisma (your choice when you gain this Dark Gift). If you have spell slots of 2nd level or higher, you can cast this spell with them.

When you cast Alter Self using this feature, some cosmetic aspect of your second form remains after the spell ends. This visibly marks you unless you actively hide or disguise it. The mark is a perceptible change such as scaly skin, stunted wings, eyes without pupils, or horns. The mark fades after you finish a long rest.

Involuntary Change. Certain circumstances can activate your Dark Gift. After you experience this catalyst, at the start of your next turn you must succeed on a DC 15 Charisma saving throw or use your action to cast Alter Self as described in the Transformation trait, even if you have already used it.