Is the homebrew weapon attack cantrip 'Blade of Hate' balanced?

Question

I have created some new cantrips which include making a weapon attack as there are only two official ones to choose from. I've tried to follow these principles based on Booming Blade and Green-Flame Blade:

• Melee weapon attack only, 5 foot range
• No unavoidable extra damage to the primary target at level 1
• Damage no more than 2 targets
• Spellcasting ability modifier doesn't have to affect the spell at all
• Only available on the Warlock, Sorcerer and Wizard spell lists

But with such a small amount of official content to compare them against, it's hard to say if they're balanced.

Is this spell balanced with Booming Blade and Green-Flame Blade?

Blade of Hate

Enchantment cantrip

Casting Time: 1 action
Range: 5 feet
Components: V, M (a weapon)
Duration: 1 round

As part of the action used to cast this spell, you must make a melee attack with a weapon against one creature within the spell's range, otherwise the spell fails.

On a hit, the target suffers the attack's normal effects, and it must make a Wisdom saving throw or become afflicted with an irrational hatred of you until the start your next turn. On its turn, it must use its action to attack you or include you as a target of or in the area of a hostile ability if it can. (Other targets may be chosen as well as you if applicable). Undead and creatures immune to being Charmed aren't affected by this effect.

At 5th level, the attack deals an extra 1d6 psychic damage to the target. The damage roll increases by 1d6 at 11th level and 17th level.

Answer 1

Blade of Hate is not balanced.

The condition of "irrational hatred" in its current state is not balanced. You can find inspiration for Conditions (PHB 290-292); you may want to compare it to Charmed and establish a reversed effect.

In its current iteration it is stronger than the 4th-level spell Compulsion (PHB 224):

Each affected target must use as much of its movement as possible to move in that direction on its next turn. It can take its action before it moves. After moving in this way, it can make another Wisdom saving throw to try to end the effect.

A target isn't compelled to move into an obviously deadly hazard, such as a fire or pit, but it will provoke opportunity attacks to move in the designated direction.

As such a creature cannot be compelled into a deadly hazard. But you could engineer situations where the creature would have to go into a deadly hazard at the off chance of making an attack or an action that targets you.

A flying person could fly through a corridor riddled with pressure plates that let the affected creature fall onto spikes, even if that creature was aware of that, under this effect it would be compelled to attack you, and likely be impaled by spikes.

If you want further inspiration on how to balance this Cantrip you could compare it to the 1st-level Paladin spell Compelled Duel (PHB 224; thank you NautArch for mentioning the spell):

You attempt to compel a creature into a duel. One creature that you can see within range must make a Wisdom saving throw. On a failed save, the creature is drawn to you, compelled by your divine demand. For the duration, it has disadvantage on attack rolls against creatures other than you, and must make a Wisdom saving throw each time it attempts to move to a space that is more than 30 feet away from you; if it succeeds on this saving throw, this spell doesn’t restrict the target’s movement for that turn.

The spell ends if you attack any other creature, if you cast a spell that targets a hostile creature other than the target, if a creature friendly to you damages the target or casts a harmful spell on it, or if you end your turn more than 30 feet away from the target.

This spell leaves you with more agency than the Compulsion spell, and if you tinkered around with the effects such:

1. disadvantage on attack rolls against creatures other than you
2. restricting the spatial limitations

Under the restraints like getting harmed etc. you could achieve a balanced version that should be weaker than a 1st-level spell because those deplete the limited resources that characters have.