Beyonders (only use if you hate your party)

Beyonders are strange creatures, hailing from regions far away from the known planes. As they have only recently been showing up, not much is known about universal traits but individuals of this "species" have shown some of these traits.

mimicry: once an attack has been used on certain beyonders, they gain a resistance to it and can use it infinitely. Anything from Magic to physical strikes can be learnt and as the fight drags on it will adapt (if certain stats are higher than it's own, it will copy it).

blinding flash: using their highly luminescent skin, some beyonders can temporarily blind any being unfortunate enough to see it at that moment. On top of this they will inflict 1d4 radiant damage to anyone within 10ft and knock them prone.

hypnotic trance: by altering the colour and level of light on parts of their skin, a few beyonders can put an individual into a trance (DC18 WIS save) only broken upon death in which the beyonder has full control over the person under the trance.

Weapon mimicry: once hit by a weapon or spell, the beyonder (if it has the mimicry trait) can make a perfect replica of that weapon (special traits and all) or spell (can only have three spells copied at a time).

Body morph: If within range, the beyonder will change the shape of it's body to dodge/counter/attack you.

dimensional sever (30ft) (charges: 5/day): The beyonder can send forwards a slash in which any enemy hit by it takes 1d8 of slashing damage. But also the thing hit has to roll a DC18 DEX save in which (if they fail) they are immediately sent to a plane of the DM's choosing.