1) Big, big number 2) Cardinal 3) Ginormous quantity 4) Hyperbolic figure 5) Large number 6) Master System game 7) Metroidvania game 8) Sega franchise 9) Side-scrolling platform game 10) Unreal number 11) Very large indefinite number 12) Whole slew of 1) Slew 
[video game] Zillion, known as lit. Red Photon Zillion in Japan, is a space adventure platform video game designed for the Sega Master System as a companion for the Zillion anime in 1987. The game is a free-scrolling platform/adventure in the vein of Metroid. It also has objects to be inspected and the need to enable things by accessing cod...
Zillion is slang for a very large number.
[adj] - very large indeterminate number
jillion noun a very large indefinite number (usually hyperbole); `there were millions of flies` adjective very large indeterminate number; `a zillion people were there`