Is there anything that I can use or make that is breakable and makes pressure?
BOYL, as long as you contain it should work
Really any gas would work
oilconductors when sparked too
BOYL + URAN, DMG, SPRK, THDR, NEUT + DEUT/PLUT
Snow(sing)
NBLE in a 2 pixel thick CRMC container and surrounded by INSL when repeatedly sparked in a TTAN container for high pressures