Ratatouille is a custom Machine Gun.
Ratatouille is the custom version of HMG50. It has similar stats as its standard version: low rate of fire for a machine gun and high accuracy and range. It also additionally has power to affect enemies with Poison status effect, however there is only chance for the actual effect, like with every other custom machine gun.
This is also a name of a meal, and a Pixar's movie