Klepto is a crab that is the antagonist in the game Puffle Launch, who tries to steal Puffle O's with an Aqua Grabber-like machine which he also stole. He appears in every sixth level in the game. In levels 6, 18, and 30, defeating him is optional. In levels 12, 24, and 36, he is required to be defeated in battle to progress. He also makes a cameo in Jetpack Boost in both Club Penguin App and Club Penguin Island.
His name, revealed in the Club Penguin Top Trumps Pack, could possibly be a pun on the word kleptomaniac, a living thing who likes to steal things. In this case, the crab likes stealing O' Berries.
In stage 6, he floats over the goal ring and attempts to grab it. If hit by a puffle, he slowly flies away. After being hit several times, he is defeated.
In stage 12, he steals the goal ring, then flies over to the main part of the level where he flies back and forth over multiple cannons. After being hit several times, he is defeated and releases the goal ring.
In stage 18, he flies through the stage, using a magnet to steal Puffle-O's, which cannot be recovered. After being hit several times, he is defeated.
In stage 24, he steals the goal ring, then flies in a circle around the stage. If he is hit, he swings around a giant anvil to defend himself. After being hit several times, he is defeated and releases the goal ring.
In stage 30, he follows the puffle around, using a gravity box to switch gravity, which allows for progress through the stage. If the puffle gets close, he quickly flies back and changes the gravity, attempting to make the puffle fall out of the level. After being hit several times, he is defeated, and gravity is no longer changed.
In stage 36, he steals the goal ring, then flies within a barrier of floating boxes with plants. If he is hit, the boxes all fly outward before quickly flying back to him. After being hit several times, his Aqua Grabber ship is destroyed, except for the cockpit, which he flies to the next part of the level with.
After flying away, he lands on the Box Dragon, and takes control of it. He uses it to shoot flaming, exploding boxes at the puffle, which must be used to bounce over and hit him. Every time he is hit, the flaming boxes explode faster. After being hit several times, he is defeated and releases the goal ring.