Well, if we start off from 10…

10. Lugia. You see, in Johto, parents used to tell children stories about Lugia—specifically that it would drag misbehaving children to its dark, cold lair beneath the Whirl Islands. In theory, this was supposed to keep children in line; in practice, it simply gave many of us nightmares.

9. Suicune. Technically all of the Johtonian legendary beasts because of their duty as judges for humanity, but Suicune is the least frightening. After all, while it, too, flies across the region to determine our worthiness and smite those who aren’t quite as worthy, it also purifies water, helps with crops, and is generally the most merciful of the three.

8. Entei. Like Suicune, Entei’s duty is also to wander the region and smite the unworthy in an attempt to purify Johto and prepare it for Ho-oh’s return. Likewise, it controls volcanoes, and it’s said that volcanic activity occurs whenever it roars. As both Kanto and Johto are highly volcanic regions, this of course is cause for worry alone, but at the very least, Entei is a very justice-minded pokémon and (according to legend, anyway) prefers to simply observe than exercise its power.

7. Raikou. As with the other two beasts, Raikou is also a judge of humanity, but unlike the other two, it freely uses its power against those who cross it. Some say it’s because its power is neither beneficial to humanity (like Suicune’s) or sourced from the earth itself (like Entei’s) but rather both destructive and contained wholly within its own body, allowing it to use it whenever it wishes. Regardless of the cause, Raikou’s Thunderbolts are about as potent as the Thunderbolts from a thousand pikachu, so it’s not a pokémon I would wish to cross myself.

6. Celebi. Despite its cute appearance, Celebi is not a pokémon you would want to encounter. It’s notoriously capricious, and with its time-traveling ability, it’s been said that anyone who encounters it may disappear, perhaps lost through time. I don’t think I need to go into the repercussions of that anytime soon, no pun intended.

5. Dialga. On that note, Dialga is essentially like Celebi in that it has the power to control and travel through time. It’s just that Dialga is the embodiment of time itself, and with that much power, who knows what it’s capable of doing to any human in its presence?

4. Palkia. As Dialga’s partner, Palkia’s abilities are just as potent but tied completely to space. However, as such, Palkia’s powers aren’t well understood, even within its religious contexts. According to stories, Palkia has the power to transport anything across space in an instant, as well as alter the very fabric of reality itself. In this sense, Palkia may have the ability to erase anything it deems unworthy from existence itself (thereby removing it from its own domain of space), if not simply transport that nuisance across space to the very edge of the universe.

3. Azelf. Granted, all three of the Lake Guardians of Sinnoh are terrifying in their own rights (Mesprit can remove a human’s ability to feel emotion upon physical contact, and Uxie has the ability to completely erase the memories of anyone who looks into its eyes), but Azelf’s power is by far the most terrifying. According to Sinnohan belief, if a human being harms Azelf, even by accident (apparently aside from consensual battling), Azelf will remove that human’s will to do anything. Not just live, mind you, but literally do anything at all. Imagine suddenly being trapped in your body and not even minding.

2. Darkrai. My reasons for this are very much like Azelf’s. According to Sinnohan folklore, Darkrai has the ability to trap anyone within an unending nightmare. Thus, the victim is forced to spend the remainder of their lives dreaming horror after horror, all while their bodies in the physical plane waste away. Azelf is one thing; at least you don’t even care that you waste away. But with Darkrai, you’re aware of yourself. You may not be fully aware that you’re dreaming, but you know you want your torment to end. The worst part about it is that attempting to wake you through normal, conventional means (anything from shaking you to using a pokémon’s Dream Eater on you) won’t work according to that very same legend; the only way to wake you is to obtain a feather from the equally rare and difficult-to-find Cresselia.

1. Fearow. For … for reasons.