Animate Powerful Corpse

This spell creates an undead servant. Choose a pile of bones or a corpse of a non-undead, non-construct, medium or small creature of CR 1/2 (or below) within range. Your spell imbues the target with a foul mimicry of life, raising it as an undead creature. The target becomes a Skeletal creature if you chose bones, or a Zombified creature if you chose a corpse.

The statistics of the creature are as follows. The Intelligence, Charisma, and Wisdom of the creature are the same as a Skeleton (if you chose bones) or a Zombie (if you chose a corpse). Half the max Hit Points of the original creature are both it's current and maximum Hit Points when summoned.

As a Zombie, the creature forgets all spellcasting and abilities with complex thought required, but retains all other abilities and acquires "Undead Fortitude: If damage reduces this creature to 0 hit points, it must make a constitution saving throw with a DC of 5 + (the damage taken), unless the damage was a critical hit. On a success, this creature is instead reduced to 1 hit points." Strength is the same as the original creature's, Constitution and Dexterity decrease by 2.

As a Skeleton, the creature may retain their spellcasting of level 3 and below, but loses all abilities that rely on internal organs or other non-bone parts (AKA: no Dragon Breath, Troglodyte Stench, etc). Strength and Constitution reduce by 2, Dexterity gets +1

On each of your turns, you can use a bonus action to mentally command any creature you made with this spell if the creature is within 60 feet of you. You decide what action the creature will take and where it will move during its next turn, or you can issue a general command, such as to guard a particular chamber or corridor. If you issue no commands, the creature only defends itself against hostile creatures. Once given an order, the creature continues to follow it until its task is complete.

The creature is under your control for 9 hours or until you cast this spell again, after which it stops obeying any command you've given it and is immediately hostile to you. To maintain control of the creature for another 9 hours, you must cast this spell on the creature again before the current 24-hour period ends. This use of the spell reasserts your control over the creature you currently have animated with this spell, rather than animating a new one.

You can also choose to forgo having to reassert control from 9 hours passing if you take one of these downsides.

(Zombies) "Dead-Rot: This creature takes 1 damage (automatic, no resistance or immunity possible) every minute it is not within cold temperatures. This damage increases by 1 for each of the following circumstances: Swamp, been dead for longer than a day before reanimated, it's summer (in game), and/or it has used it's "Undead Fortitude" ability. This can be easily avoided with spells such as "Prestidigitation" or by keeping them in a cold area like a cave.

(Skeletons) This creature retains it's personality, sentience, memories, and goals if any previously resided in the target.

At Higher Levels: The CR maximum of the creature you control increases, at 5th level the CR increases to 1. Afterwards, each level increases the CR by 1. Either that OR the number of reanimated creatures increases by 1 for every level beyond 3. You cannot do both.