From the Super Mario Wiki
Rocky Wrenches are mole-like enemies, said to be a type of turtle, that pop out of manhole covers and attack foes by throwing wrenches. Rocky Wrenches work for Bowser's Koopa Troop, often appearing as guards on the organization's vehicles.
 Super Mario series
 Super Mario Bros. 3
Rocky Wrenches first appear in Super Mario Bros. 3 as enemies on Airships, tanks, and ships belonging to the Koopa Troop. Upon sighting either Mario or Luigi, a Rocky Wrench will pop out of its hole on these vehicles and throw wrenches at them before descending back into its hole.
In most cases, a defeated Rocky Wrench will reappear, even when defeated by a stomp (it can be said they are stunned by being stomped). However, some Rocky Wrenches are permanently defeated when attacked.
 Super Mario Galaxy
Rocky Wrenches also appear in Super Mario Galaxy as enemies in the Gusty Garden Galaxy and the Battlerock Galaxy, where they attack by throwing wrenches as before. If the player were to approach the trap door where Rocky Wrenches attack from, they will not surface, only doing so if the player is some distance away. Here, the player must shoot a star bit at them from a certain distance or perform a Ground Pound to knock them over and then jump on or star spin them to defeat them. The Rocky Wrenches in this game do not have shells on their backs like Super Mario Bros. 3, so they look like small Undergrunts with blue caps who throw wrenches. They are known as Mogu (モグ) in Japan, matching Undergrunt's Japanese name Moguhei (モグへい), so they are intended to be different enemy creatures.
 New Super Mario Bros. Wii
Rocky Wrenches also appear in New Super Mario Bros. Wii on the Airship of World 6. Their behavior is largely unchanged from their Super Mario Bros. 3 incarnation, though they can be frozen by Ice Mario. They are also defeated permanently when attacked. Rocky Wrenches have a nearly identical appearance to a Monty Mole with goggles; as with the Super Mario Galaxy variation, they don't appear to wear shells.
 Super Mario 3D Land
Rocky Wrenches make a reappearance in Super Mario 3D Land. Though they are commonly found in Airship stages, they appear in several levels in the game. Their appearance is the same from New Super Mario Bros. Wii and conduct the same tactics of throwing wrenches as well, but some appear in pipes, some throw Bob-ombs, and some even throw Coins. Unlike other games, the wrenches they throw can be stomped on harmlessly, destroying them.
 New Super Mario Bros. U
Rocky Wrenches appear in the Wii U title New Super Mario Bros. U with the same design and attacks New Super Mario Bros. Wii, they only appear in Boarding the Airship of the Meringue Clouds. They are one of the few enemies that don't appear in New Super Luigi U.
 Mario Kart series
 Mario Kart DS
In Mario Kart DS, Rocky Wrenches appear as obstacles on the Airship portion of the Airship Fortress. Popping out of their holes at random, these Rocky Wrenches can cause a kart to spin out of control if run into.
 Mario Kart 7
In Mario Kart 7, Rocky Wrenches appear on the retro course, Airship Fortress. They also appear in Battle Course 1. Here, they look like their New Super Mario Bros. Wii and Super Mario 3D Land appearance. They act like they did in Mario Kart DS.
 Paper Mario: Sticker Star
Rocky Wrenches make their Paper Mario series debut in the Nintendo 3DS game Paper Mario: Sticker Star. They only appear on Bowser Jr.'s Flotilla. In battle, a Rocky Wrench will either hide inside their manholes or have their heads peeking from the manhole. If they are hiding inside the manhole, they cannot be attacked. Rocky Wrenches, just like in previous games, throw their wrenches to attack. Sometimes after battle, a Rocky Wrench may drop a Wrench sticker.
 The Adventures of Super Mario Bros. 3
On the television series The Adventures of Super Mario Bros. 3, Rocky Wrenches appear in several episodes, most commonly as the guards of Bowser and the Koopalings' Doomship, although they are also shown to work on tanks and the Doomsub as well. A Rocky Wrench, whose dialogue consists of nothing but menacing growling, has a somewhat prominent role in the episode "Up, Up, and a Koopa", where one is assigned by Bowser and Kooky von Koopa to guard the cage that Emperor Ed, and later Mario and Luigi, are held captive in. He is bribed a Fudjie by Mario to free them, but declines.
 Nintendo Adventure Books
A Rocky Wrench competes in the International Mushroom Games as a member of a team called the Sneaks in Leaping Lizards. True to his team's name, he uses underhanded tactics in the events, cutting a hole in Roy Koopa's Magic Carpet during the obstacle course and throwing ink in his face during the Beetlebowl.
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