Just some inspiration from Legend of Zelda and Final Fantasy V
Devil Fruit: Mirage Mirage fruit
A paramecia fruit that can conjure illusions and mirages
Some rough ideas from it:
Apparitions - the user conjures up images of a person that is once dear to his opponent, like a daughter or a friend. In the end, these are phantom creations that can kill their target, once he goes too close. These will only disappear if the user's body is attacked, or if the user wants to.
Phantasma Gang - the user deceptively conjures up identical images of himself to fight and trick the foe; these images can attack, but cannot be harmed, and will disappear only if the user's actual body is hit. The amount that can be conjured depends on the user's stamina; more stamina = more images
Mirage World - the user twists his surroundings according to his own whim.. he could create anything from weapons to entire islands, and even people.. out of nothing but his imagination, and can make everything disappear whenever he feels like it... It's probably an awakening type move.
Nightmare - an awakening type move, where the user can turn anything in his environment to anything he wants... can be massive spears, axes, bats, monsters, etc.
Come to think of it, it's a bit like a more advanced version of Brulee's fruit, but w/e.