Carom

The Carom is an enemy from the ZX series. It is a spherical Mechaniloid with an impenetrable outer shell that can split into four parts. In ZX, its shell is blue with a red stripe on each shell segment. It attacks by opening its shell horizontally or vertically to reveal a glowing yellow core and firing two shots up and down or left and right, depending on how the shell opened. It can only be harmed while the shell is open. It explodes upon defeat, harming Vent/Aile if he/she is in the blast range. In ZX Advent, the only change is that the blue on the shell has become green, and it does not always fire upon opening.