The Atom
The Beetle
Ant-Man
Atlas
Rephaite
Ladybird
A revolutionary compound created by Dr Henry Pym of S.H.I.E.L.D's Owl Wing that allows the uer to alter their mass, durability, and mass according to the build ingested or inhaled.
Though initially utlised only by S.H.I.E.L.D sanctioned operatives, the Particles have since been stolen and reversed engineered and now see use by a number of agencies that have the resources available.
Users, past and present, include;
Ant-Man (Retired ID)
Ant-Man II of Raven Wing
Rephaite of The Immortals