Illusioner

The illusioner is an unused illager that may cast the Blindness or the Invisibility effects and is armed with a bow and arrows.

Spawning
An illusioner has no spawn egg in the creative mode inventory. They can be spawned only using datapacks or the in-game command. Illusioners do not spawn in woodland mansions, raids, patrols or pillager outpost. Similar to the unused giant mob and zombie horse, they do not naturally spawn in any biome, monster spawner or world generated structure.

Drops
When killed by a player, any naturally spawned equipment, including their unenchanted bow, has an 8.5% (9.5% with Looting I, 10.5% with Looting II and 11.5% with Looting III) chance of dropping and drops with a random item durability.

Illusioners also drop 1 illager ominous banner if it is a raid captain.

experience orbs are dropped on player kills.

Behavior
Although they do not naturally spawn in raids, illusioners spawned by the player attack players, adult villagers, iron golems and wandering traders within a 16*4*16 cubic area. They join a nearby raid if it occurs or join a patrol if sufficiently near a patrol captain. It attacks with its spells and its bow, firing an arrow every second. It is the only illager that can see its target through walls.

The Illusioner moves quickly and always tries to maintain a consistent distance between itself and the player, retreating if the player gets too close or advancing if the player retreats.

The illusioner has two spells: a spell that blinds its opponent and a spell that summons visual pseudo-duplicates and makes the illusioner invisible.

Casting blindness
The illusioner casts its blindness spell only if the regional difficulty is greater than 2. As result, the world difficulty setting, the inhabited time of a chunk, the total daytime in the world and the phase of the moon from the day-night cicle affects its ability.

An illusioner casts a effect that lasts for 20 seconds upon first engaging a new opponent. It signals this attack by raising its arms, making a low pitched sound and producing a black mist of particles.

The illusioner does not cast this spell more than once on the same opponent, unless it has first shifted its attention to another opponent and then back to that original opponent.

This spell resets the illusioner's spell cooldown to 1 second and resets the cooldown for the blinding spell to 9 seconds.

Unless the illusioner is summoned using commands, it cannot attack with a non-bow item in its hand, cannot use tipped arrows in its offhand slot (but can use spectral arrows) and cannot use enchanted bows.

Summoning duplicates
As long as an illusioner is engaged in combat, it casts an status effect on itself that lasts 60 seconds and refreshes the effect whenever the Invisibility's time runs out. It signals this spell by raising its arms, making a strange high pitched sound and producing a blue mist of particles.

When an illusioner becomes invisible – through this or another method – it creates 4 false duplicates of itself.

These hover and waver at short distances from the actually invisible illusioner, though they do not space themselves out until the first time the illusioner is attacked. They face in exactly the same direction as the illusioner and move somewhat in step with the original, appearing to no-clip through blocks like a vex does. Despite using the shooting animation whenever the original uses its bow, only the real illusioner can shoot and be damaged.

Eventually, if the clones were not triggered and are still bunched together, they move to new positions. The Illusioner can also do this once in a while to "refresh" the clones' positions.

When the real illusioner is damaged, its duplicates all snap back to where the real illusioner is, then quickly snap back out to new positions, making a teleporting sound, signaling the hit.

If an invisible illusioner receives the effect, all of the duplicates glow, while the true illusioner remains invisible.

When catching fire, only the invisible illusioner burns.

The duplicates dissipate once the illusioner's Invisibility effect ends.

This spell resets the illusioner's spell cooldown to 1 second and resets the cooldown for the invisibility spell to 17 seconds.

Sounds
Illusioners use the Hostile Creatures sound category for entity-dependent sound events.

Entity data
Illusioners have entity data associated with them that contain various properties.

Trivia

 * The illusioner displace sound almost is the same as the tradicional teleport sound displaced by teleportation via an ender pearl[[ or [[chorus fruit, endermen or shulkers, albeit with a slight distortion at the end.
 * Illusioners shoot backward when in a boat.
 * Illusioners hold bows in a different direction compared to skeletons or players, more diagonally.
 * The illusioner's second death sound is the same as the evoker's second death sound.
 * The illusioner is the only illager that has more than 24 health points.