Alecto's Excavating Exoskeleton

You touch a willing creature who then becomes covered in an armored exoskeleton made of bones. The exoskeleton acts like chain mail (AC 16) that the recipient is proficient in wearing, and has no minimum strength requirement.

The exoskeleton grants advantage on Strength checks and a burrowing speed of 10' (leaving behind a 5' diameter tunnel). While wearing the armor, the character's walking speed is halved and their flying speed becomes 0'.

If the caster is wearing the exoskeleton themselves, they get Advantage on their first concentration check to maintain the armor.