Gauntlet Groink

The Gauntlet Groink is a highly-dangerous groink found in Pikmin Z. This giant groink appears less like a fish, and more like a well-oiled machine: it has a rounded, spherical body, a single eye at the center of its face behind its facial shield, and four pipes on its back that release steam. It not only has a cannon-mouth typical of shot-fish, but it also has dual rapid-fire weaponry it uses to quickly dispose of threats.

Biology
The Gauntlet Groink is a titan of shot-fish species, highly advanced in attacks towards its opponents. Throughout the fight, its main attacks consist of: a charged projectile shot from its mouth, which explodes on impact and has a large blast radius; the use of a set of machineguns that shoot projectiles, similar to that of a Man-at-Legs, that ignite mostly anything they hit instead of killing them instantly; and lastly a blast of water in the form of a tidal wave from its true mouth.
 * Diet: unknown
 * Predators: unknown

Piklopedia entry

 * "The Gauntlet Groink is the ultimate doomsday weapon of groinks. So many different attacks stacked within that biomechanical shell, and all of them dealing a lot of damage. If this beast is indeed the future for groink evolution, the implications it holds are dire."

Strategy
The battle against the Gauntlet Groink is mildly complicated. The fight itself has several phases, and the boss itself is initially invulnerable and has a small variety of attacks. The Gauntlet Groink will initially begin the fight by launching explosive shells at leaders and Pikmin, which must be dodged. Eventually, the Gauntlet Groink will fire a magnetic boulder which will follow leaders and can be led into the creature to break a small portion of its armor so it may be attacked by Pikmin. The armor will not reappear at any point during the boss fight, and the more armor is broken, the more weakpoints the boss has.

Each time the Gauntlet Groink shakes Pikmin off of itself, its machineguns will trigger and begin firing after a short delay. The barrage of bullets can be avoided simply by running around until the creature ceases fire. Once the Gauntlet Groink's health reaches seventy-five percent, it will begin to occasionally fire a series of non-magnetic boulders in rapid succession. At fifty percent health, the creature will begin to occasionally create a massive wave of water using its mouth which can be avoided by seeking high ground. Upon death, the Gauntlet Groink and its weaponry will malfunction and deactivate, allowing Pikmin to carry it.