Dwarf star is a rare type of metal alloy that is extremely strong, dense and powerful. It has been used by Ray Palmer in the creation of the A.T.O.M. Exosuit and the Steel suit. It can also be used to generate a blue energy in the form of blasts, shockwaves or even size alteration beams; which notably is used by the A.T.O.M. suit's weapons.
Quentin Turnbull developed bullets laced with the alloy, that could cause massive explosions of blue energy on impact and even bypass Nate Heywood's enhanced durability to wound him. Due to its density rendering the alloy extremely heavy, Superman made a key to his Fortress of Solitude out of a condensed version of this alloy that only immensely strong beings can lift, as it weighs approximately a million tons.
Dwarf star is one of the rarest, most powerful and dense metallic alloys in the entire multiverse.
DC's Legends of Tomorrow