The power to control undead has evolved, and the user's mastery over it has grown significantly. The user now starts with 25 slots for undead and receives an additional slot every month. At will, the user can absorb their undead to obtain a temporary power boost and a minor permanent power boost, along with a healing effect.
Wraith
You can use your slots to turn any ghost you summoned into a wraith. Wraiths can fly at a low altitude and transition between intangible and tangible states at will. They retain any power they had in life. They have autonomy but are instinctively loyal to you.