Trickster's Chimera

You create the image of a creature that is no larger than a 30-foot cube. The image appears at a spot that you can see within range and lasts for the duration. It seems completely real, including sounds, smells, and temperature appropriate to the thing depicted. You can't create sufficient heat or cold to cause damage, a sound loud enough to deal thunder damage or deafen a creature, or a smell that might sicken a creature (like a troglodyte's stench).

Any creature that failed the illusions INT saving throw after the spell was cast will be effected by the illusions attacks, any creature who succeeded will not be effected or damaged, but can still see it for it's appearance. The form the caster takes is inherently threatening and must be able to reasonably do a 15-foot cone of damage, whether that be a dragon's breath, a centaurs halberd slicing in an arc, or the blasting of concussive energy from a water elemental. As an action the caster may attack the creatures who failed the Intelligence saving throw prior. The illusion attacks in a 15-foot cone against the creatures who then make Dexterity Saving throws, taking 4d8 Psychic damage on a failed save or half as much on a successful save, though this does not dispel the illusion for them.

A creature that uses its action to examine the image can determine that it is an illusion with a successful Intelligence (Investigation) check against your spell save DC. If a creature discerns the illusion for what it is, the creature can see through the image, and its other sensory qualities become faint to the creature.

At Higher Levels. When you cast this spell using a spell slot of 7th level or higher, the spell lasts until dispelled, without requiring your concentration, though any new creature that see's it will need to make the initial Intelligence saving throw.