The so-called "MARPA Memory Gun," or "proton gun," was summoned from an alternate timeline using a particle accelerator at Stanford and Anunnaki glyph geometry constructed by Carl Fletcher and Rich Talbot with advice and guidance from the Old Man. It functions in a manner similar to SANDMAN's ikoter gun, but without the fine tuning and with none of the safety equipment. If the SANDMAN ikoter is a carefully crafted military-grade rifle, the MARPA Memory Gun is a black market sawed-off shotgun.