Xylaris, the Veil Weaver

{u} Create a 2/2 blue Illusion creature token with "When this creature becomes the target of a spell or ability, sacrifice it."

Whenever Xylaris, the Veil Weaver enters the battlefield or attacks, you may choose a target creature.
That creature becomes an illusion in addition to its other types until end of turn and gains "This creature can't be blocked."

{2}{u}{b} Exile target creature.