Dwarf star is a rare type of metal alloy that is extremely strong 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 energy blasts or shockwaves, which notably is used by the A.T.O.M. suit's weapons, while 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, the latter without the explosion.
DC's Legends of Tomorrow