1. I don't like the way ghosts attack
2. a) it doesn't look right
b) how they deal damage while inside (wouldn't it be simpler to just kill the creature immediately)
3. I probably wouldn't change the attack (since the concept is good:) ), but I would add an ability that would kill at least one creature - this will create balance issues, and to solve them, you'd have to slightly lower the ghosts' stats.
Awaiting your assessment...
После инквизиторы калечили мне тело
Все восстало против молодого некроманта
Сделав меня мучеником моего таланта