The Stapler, as his name implies, resembles a black stapler. His personality is similar to a dog.
The Stapler makes his first appearance turning a Koopa Troopa into a Folded Soldier. Paper Mario and Olivia can watch this if they peep through the window in the dungeon of Princess Peach's Castle. King Olly later summons the Stapler to attack the heroic party in his castle. Paper Mario eventually defeats and destroys the Stapler with his 1,000-Fold Arms by snapping him open.
The Stapler attacks by biting to strike Mario. He can also launch his Staplers to trap Paper Mario, enabling him to take an extra turn to strike with Untag Wag if Paper Mario flubs his guard. Paper Mario has to damage the Stapler by attacking him. The Stapler will fire staples from his mouth if Paper Mario is too far away from him for the Stapler to use his bite. However, there are a finite amount of staples for the Stapler to use in his attacks. If he runs out, the boss will have to recharge the staples, which is when he will be the most vulnerable to a Rush attack. The Stapler has three types of staples, with gold being the strongest, grey being the weakest, and red being in the middle.
After he loses considerable chunks of his stamina, the Stapler will change the staple types. Paper Mario has to destroy the Stapler by Rushing him with the 1,000-Fold Arms technique and then snapping him open.
- Quite unusually for the Legion, the Stapler is the only boss from the Legion of Stationery that does not speak at all.