Boss Kucurbium is known to be the mother of all motherships and are about four times the size of a regular Kucurbium. But luckily, this alien can only be found in the last wave of the Level Invasion Gate and in the Galaxy Gate Kappa. Unlike other Alien, the Boss Kucurbium is actually larger in size rather than being only more powerful and having a red aura.
The Boss Kucurbium shoots in bursts of roughly 5-8 shots rather than a single volley. This is more than adequate to take out even an Full-EliteGoliath with ease. It is rather wise to shoot these down with at least 25+ players in the Level Invasion Gate. A Boss Kucurbium's speed is roughly the same as a Kristallon.
Unless you attack it from the beginning, it's rewards aren't as good as the normal Kucurbium because if you shoot it at it's Critical Health, everyone's already got a bigger part of the reward than you do. But be cautious when shooting first due to it targeting you, dealing an average of 46,000 per hit!
When killing a Boss Kucurbium (or it's smaller counterpart) and having the rectile red on it, should give you a random 10 hour booster. However, this is near impossible to achieve, merely luck, due to all of the players it requires to take down.
Considering it's size, a Boss Kucurbium is quite fast.
It is not uncommon to find yourself being chased around the map by this massive mothership, if it happens, use an EMP as soon as possible and begin to repair.