Space Fiends: Star Stalker!

I did a post about using AD&D Fiend Folio monsters in a science fiction context. This post is another follow-up.

No. Appearing:1-2
AC: 3
Hit Dice: 6
Saving Throw: 12+
Attack Bonus: +5
Damage: 1d8/1d8
Movement: 30'/40' fly
Morale: 12

Stellar phantoms are strange lifeforms of pure plasma. Some technological artifacts of long-dead civilizations allow the summoning and command of these creatures that otherwise live in the solar winds and have little interaction with biological life.

Their form is mutable, but phantoms often take the form of reddish humanoids shrouded super-heated gas. They tend to travel through space as balls of pure plasma and are able to mimic the forms of other humanoids (though obviously, they would never be mistaken for them). 

Phantoms attack with their "claws", but they can also grapple a target and pull them close for 10 points of heat damage. As creatures of plasma, they are immune to heat, fire, or plasma weaponry. Cold attacks add 2 points of damage per die. If a stellar phantom is reduced to 10% of it's hit points, it will explode for 4d6 points of damage.