Undead Companion

This spell creates an undead servant. Choose a corpse of a creature you can see. You touch the creature in a long ritual. Your spell imbues the target with a foul mimicry of life, raising it as an undead creature.

You roll a spellcasting ability check against the former creature's challenge rating + 12 If the creature does not have a challenge rating, use the character level instead. If your roll is higher, the creature rises as your undead companion, otherwise the spell fails. The DM decides the exact stats of the creature. As a bonus action you can give any command to your companion and it will follow to the best of its ability. You can only have one undead companion at a time.

If the companion's HP drop to 0 the creature dies again and the spell ends.

The spell lasts until the companion or its master dies or until disspelled. When the spell ends, the undead companion falls and behaves like a regular corpse again.

At higher levels: If you cast this spell on a spell slot of 7 or higher, you can add +1 to your ability check for each spell level above 6.