Nightmare: transform: turn into a medium sized goop puddle that increases your speed greatly. Turn back into the normal nightmare after a few seconds. Helpers: summons goop sanses who have low hp and throw goop/bones/blablabla. costs some stamina Screaming blaster: summon a giant blaster in the middle of the map to scream with a shockwave, costs a lot of stamina and has a large area of attack (attack idea inspired by au sans battles) Passive: negativity : attacks weaken for every low LOVE frisk, attacks become more powerful for every high LOVE frisk. (optional)

Nightmares: Passives: a small goop 1 attack: tentacle stab It's a meele attack that deal 5-20 damage 2 attack: tentacles SMASH a tentacles that smash the ground around nightmare and have Aoe (deals 2-5 damage every second) the smash effect will be there for 3 second 3 attack: tentacles zone Spawn a zone of tentacles on the enemy and deals 8 damage 4 attack: I'M IMMUNE become immune to frisk attack for 4 second 5 attack: let me spawn My helper Spawn dust, killer or horror they attack the nearest frisk near them 6 attack: RAGE makes nightmare rages and make him have faster cooldown and make his damage deal more ( he will be in that state for 6 second)

Nightmare sans will sometimes spawn a spinning tentacle Dream sans will spawn arrows instead of gaster blasters and shoot with 3 arrows

Idk attackd but you can too make enraged nigthmare sans for phase 2

For dream he should have a meter that buffs his attacks it should be gained from not using attacks for 10 seconds

The nightmare could have an ability that would expand a domain, leaving the map contaminated with tentacles, and covering enemies with tentacles that deal damage per second. I really like your games :)