Klefki

The official category is Key Ring Pokémon, and it literally describes what’s there: a metal ring with four keys hanging from it, two eyes, and a keyhole-shaped mouth. Twenty centimeters, three kilos.

Pokédex entries keep coming back to the same obsession. It collects keys. When something attacks it, it shakes them so they jingle, using the noise to intimidate its attacker. If someone gives it one, it gets very happy, although its expression twists when it turns out not to be a master key. It never lets go of its own keys under any circumstances, which is why people entrust it with their safe keys. Other entries are less flattering: its calm nature doesn’t stop it from sneaking into other people’s houses to steal keys.

It eats metal. It inserts the appendage on its head into gaps and absorbs the ions. It lived in mines until the minerals it fed on became scarce, then moved into human settlements.

It doesn’t evolve and doesn’t come from anything. It’s a single-stage species, number 707, introduced in Generation VI.

The 470 points are split into 57 HP, 80 Attack, 91 Defense, 80 Special Attack, 87 Special Defense, and 75 Speed. None of that is killing anyone. The hole is in its HP: with 57, defenses of 91 and 87 perform quite a bit worse than they promise on paper.

What keeps it afloat is Prankster, which gives its status moves priority over everything else. With that, Spikes goes up on the same turn it comes in, and Thunder Wave paralyzes a faster opponent before that opponent can move. Light Screen and Reflect, both available by TM, go up just as quickly and stay in place after Klefki has already gone down.

Its typing helps it get in. Steel and Fairy give it immunity to Poison and Dragon, a long list of resistances, and only two weaknesses: Fire and Ground.

Smogon analyzed it in OU during Generation VII with Spikes, Thunder Wave, Play Rough—which it learns at level 40—and either Foul Play or Magnet Rise in the fourth moveslot. Play Rough was there for a specific reason: starting in that same generation, status moves boosted by Prankster fail against Dark-types, and without a move that hits them, Klefki is left staring. The other things that hold it back are Ground-types, immune to paralysis and already marked as a weakness; Excadrill, which clears its Spikes with Rapid Spin; and Taunt, which shuts down its entire turn.

One Egg Group, Mineral, which pairs it with fossils, gears, and assorted scrap from the Pokédex. The gender ratio is split down the middle, with 50% female, so getting the mother isn’t the bottleneck it is in other lines.

Twenty hatching cycles, about 5355 steps. Two egg moves come from the egg, and both have a use: Magnet Rise, which covers its Ground weakness for five turns, and Switcheroo, which swaps the opponent’s held item and works with Magician, its Hidden Ability, which steals the item from the Pokémon it hits.

It doesn’t evolve. There’s no level, stone, friendship, or time of day involved: what hatches is what you get. It shares that single-stage status with Mawile, although Mega Evolution gave Mawile an out.

The habitat field is blank, which fits a species the Pokédex itself describes as having moved from mines to towns; in Kalos, you look for it on Routes 15 and 16. Its catch rate is 75, an in-between number: neither the 255 of something you catch without looking nor the 45 that forces you to leave it on one HP. It gives 1 Defense EV and has the Fast experience growth rate.