Grobot X

Grobot X is a boss in the game Mario & Luigi: Dream Team. It is the X boss version of Grobot that can only be faced in the Battle Ring. Grobot X is required to fight in the main story in order to get the Zee Feathers for the Ultibed. You can actually fight Grobot X before going on the Utilibed quest or even before you go to Wakeport (the bridge is fixed after you beat Robo-Drilldigger). The other bosses can't be fought yet and you have to beat Grobot X again to get the Zeekeeper Feathers.

Battle

Grobot X's attacks are identical to Grobot's. It will fire spheres of water that can either be small or large, the small ones bounce at Mario and Luigi's feet which they'll have to jump over and the large ones bounce over them. It can also turn around and charge at one of the Bros. which requires them to counter with their hammer. Additionally, it may chase the Bros. into the foreground of the battlefield while firing water spheres at them to try and cause them to trip.

Grobot X is susceptible to critical damage from the Slingsniper when aimed correctly.