Conjure Spectral Monstrosity

You summon a spectral version of a monstrosity of your choice of challenge rating 2 or lower at a point you can see within range. The summoned creature rolls it's own initiative and acts on its own turn. The creature is also friendly to you and your allies. It has all the stats and abilities of the chosen creature minus its normal immunities, vulnerabilities, and resistances. Instead, the summoned creature has resistance to piercing, bludgeoning, and slashing damage,  and vulnerability to all magic damage. As a bonus action on each of your turns, you may mentally direct the summoned creature to attack a creature of your choice on your turn.  If no command is given, the summon attacks the nearest hostile creature on it's turn. Any types of elemental damage that the normal version of the monstrosity may wield, the spectral summon deals as cold damage, and all physical damage it would deal becomes psychic damage. When the spell ends or concentration is broken, the spectral monstrosity disappears.

When cast at 4th level or higher, the summoned monstrosity may be of challenge rating of one higher per spell slot above 3rd.