Make Antimatter more reactive. It should explode rapidly, but not too much to don't crash saves. Also, Quarks (QURK) would be intresting. In positive preassure it would create NEUT/PROT or even HYGN (with high temp and THDR) randomly and some radiation. It would have 4 types (it depends on tmp) and different colours (from orange to white). Moves very fast. In negative preassure it would make Antimatter. You can also add more reactions for it.

Thank you. Yea, that's good idea to make antiparticles and more elementary particles. It would be good for atomic/explosions saves. Good idea is to add a new type of elements. ELEMENTARY PHYSICS with atom symbol. There should go all energy particles (expect neutrons) and other elements from atomic physic.