Elite X-Naut

From the Super Mario Wiki

Paper Mario: The Thousand-Year Door Enemy
Elite X-Naut

Max HP	10
Attack	5
Defense	1
Location(s)	X-Naut Fortress
Log	The pinnacle of the X-Naut troops, this soldier tackles and throws potions. Elite X-Nauts may be enhanced with nutrients developed by X-Naut PhDs.
Items	Stopwatch, P-Up, D-Down
Moves	Body Slam (5), Potion (Huge)
Tattle	That's an Elite X-Naut. This guy is the creme de la creme of the X-Nauts. Max HP is 10, Attack is 5 and Defense is 1. He'll use regular attacks as well boosting his power or size. Elite X-Nauts are tough, but you just have to smack away until they go down.
Bestiary 108 109 110

Elite X-Nauts are high-ranking soldier X-Nauts and of course, the strongest X-Nauts. Unlike the Trooper X-Naut or the PhD, this type of X-Naut wears a red-and-black uniform with a white X to signify their rank. Judging by their rank, they are usually sent on special missions. One of their usual tasks is guarding their Headquarters on the Moon. The Elite X-Naut is much tougher in battle than a standard X-Naut.

The first time Elite X-Nauts are seen on The Moon, two of them attack Mario so they "can get all the credit for killing Mario". This, however, was taken from the first Paper Mario game as two Koopatrols had the exact same conversation.