Cascoon

Of the two branches that come from Wurmple, this is the one that ends in a moth rather than a butterfly. When it reaches level 7, the caterpillar splits down one of two paths, and the one that falls on this side wraps itself completely in the silk it releases from its mouth until it becomes a purple ball measuring 70 centimeters and weighing 11.5 kilograms, with two red openings at eye level.

The Pokédex entries insist on two ideas. The first is material: the silk gradually hardens, and when the shell starts to crack, it means there isn't long to go before it emerges. The second is resentment. If it's attacked while enclosed, it doesn't move, even with heavy damage piled on, because moving would use up the strength it needs to complete the change. It endures and takes note: it never forgets who hit it while it was helpless, and when it evolves, it goes looking for them.

The official category, Cocoon Pokémon, describes a state rather than an animal. It's a three-level phase, from 7 to 10, and the purple covering announces the poison of Dustox long before that type appears anywhere.

205 base stat points spread across six slots leave little room to work with. The high figure is Defense, 55, followed by 50 HP and 35 Attack; the rest sink to 25 Special Attack, 25 Special Defense, and 15 Speed. With that Speed, it moves last against practically anything, and that total is among the lowest a Pokémon that has already evolved can have.

The movepool finishes the job. Three moves over its entire lifetime: Iron Defense, which it knows from the start and which raises the stat that was already its best; Poison Sting at level 1, with 15 power; and Tackle at 6, with 40. It can't learn any TMs. And there's one detail that sums it up: despite being pure Bug-type, it doesn't have a single attack of its own type, so it can't even get the same-type attack bonus.

Shed Skin is the only ability with any substance. It cures status conditions by shedding its skin, which fits a body changing layers from the inside, but without anything to restore its health, that prolongs the process instead of solving it. Defensively, pure Bug resists Fighting, Ground, and Grass while leaving it open to Fire, Flying, and Rock; with 25 Special Defense, any special move cuts straight through it, whatever its type.

Where it does its job is outside serious battling. Defeating it gives 2 Defense EVs, and with a catch rate of 120, forests are full of them, so it works as a cheap training dummy. In a normal playthrough, it's an interlude: three levels with Iron Defense learned and little else to do with it.

A single Egg Group, Bug, and a clean 50% gender split mean any compatible pair will do, and nobody has to hunt for the female. Its 15 Egg Cycles work out to roughly 4080 steps, one of the shorter stretches in the Pokédex, which makes sense for something that's going to go through two evolutions before level 11.

Nothing special comes from the Egg: the Egg Move list is empty, as are the TM and Move Tutor lists. And whatever hatches will be Wurmple, which is where the real issue lies. The branch the caterpillar takes on reaching level 7 depends on an internal value the game assigns when it generates it—the personality value, called the Encryption Constant in recent titles—which isn't shown on any screen and can't be changed by the player. In practice, it's a coin toss between this and Silcoon. Hatching twenty Eggs doesn't tilt the odds.

What comes afterwards has no trick to it: reach level 10 and it becomes Dustox. No item, no time window, no friendship.

Its habitat is the forest, and a catch rate of 120 puts it in the softer half of the table: a regular Poké Ball with some damage dealt beforehand will usually do. It grows at a medium pace and gives 72 base experience when defeated.