Note: all the traits and abilities of this monster are based of the CR. ect: the hosts CR is 3,witch means the the number of CR dices is 3. Basically xenomorhs traits and attacks uses the CR as number of dices.

Host like. Xenomorph can only exist when he was born from a host. That host has to have a mouth or jaws or any hole thats used for eating, and the host has to be tiny - large, monstrosity, beast, dragon, humanoid, giant or abberation. Xenomorph gains its hosts size, traits, actions, bonus actions, reactions, legendary actions and mithic actions. Xenomorph also gains all resistences, immunitys, senses and proficiencys from its host. Except for fire resistence or  fire immunity, xenomorph will always be vunerable to fire.

Armor class. Xenomorphs armor class is its hosts + 2.

Challenge Rating. Xenomorphs CR is its hosts +2.

Xenoboost. Xenomorph takes All Ability scores from its host and adds + 4 to all of them, this doesnt apply if the score is already 30. Xenomorph also gain its hosts HP +10 + CRd6. Xenomorph also recives its hosts passive perception + 2.

Acid blood. Xenomorphs blood is acid. whenever he recives a melee attack with slasing or piercing damage he damages the attackes with CR + Con. modifier acid damage. And the place where xenomorph was standing when damaged be Pearcing, Slashing damage is now difficulte tarrain and any crature that walks on it gets 1d4 Acid damage.

Alien biology. Xenomorph can not heal by potions or other creatures help. except for cantrips and spells.

Spellcasting. Xenomorph can cast any spell its hosts could.

Multiattack. Xenomorph can do one of its hosts actions and one of its own actions

Host Action. Xenomorph can perform any action of its host.

Acid spit. Melee Attact: Con modifier + 1d20 to hit, Reach 10 ft., Hit:? (CRd4 + CON. modifier) Acid damage.

Tail Attack. Ranged Attack: STR. modifier + 1d20 to hit, reach 15ft., Hit:? (CRd6 + STR. modifier) Piercing damage.

Claw Attack. Melee Attack: STR. Modifier + 1d20 to hit, reach 5 ft., Hit:? (CRd4 + STR. modifier) Slashing damage.

Inner jaw. melee Attack: STR. Modifier + 1d20 to hit, reach 5ft., Hit:? (CR d10 + STR modifier) Piercing Damage. this action can only be used on target that has condicion grapple, prone, charmed, frighened or blinded.

Hosts Bonus Action. Xenomorph can perform any of its hosts bonus actions.

Call For Help. Xenomorph does cry for help(1d20 roll) Failure witch is lower than15 : absolutely nothing happends. Succese witch is higher thay 15: Xenomorph calls 1d4 xenomorphs of any host, this bonus action can only be used when the xenomorph is alone and does not have any allies and xenomorphs called allies must have equil or lower CR than him.

Host Reaction. Xenomorph can perform any reactions it host had.