Vael constructed a personal planar stronghold called the Axis Vault—a floating stone temple stitched to the folds of his soul. Accessible as a bonus action via a sigil or phrase, this dimension is:
Always safe from outside intrusion (except divine-level threats)
Fully furnished with arcane tools, alchemy benches, and planar maps
Let's him long rest, store artifacts, and conduct rituals without interference
He may use Planar Tether to pull a willing creature inside or send stored items through minor tears in reality