Trained on 438 gelbooru images for 5840 steps. I made this for a request, and it worked out pretty well.
You shouldn't need a hard trigger, but it doesn't hurt to to add:
Yellow Sclera, Sharp Teeth, Blue Skin, Blue Body, Red Hair, Ponytail, Eyepatch
Casual outfit:
Black Tank Top, Jeans
Undying:
Undyne the Undying, Armor, Spear, Weapon, Polearm
Deltarune:
Deltarune, Policewoman, Police Uniform, (Eyepatch in negative)
Has a couple bugs but nothing inpainting can't fix.