Game Freak has decided that it's time for a complete reboot of the Pokemon franchise, and they've put you in charge of deciding who survives the Poke-purge.
The rules are as follows:
>You must reduce the total number of Pokemon down to 151 exactly. Alolan Forms count as their own Pokemon, and Megas have been removed from the game.
>You must keep 3 starters, one fire, one water, one grass. These are the only starter lines that you can keep, all others must be discarded.
>Every type must be represented at least once.
>You must pick a single Mythic to keep, and only one.
>There must be at least 4 Legendary Pokemon, not including your Mythic.
>You can't selectively cut Pokemon out of an evolutionary line. If one member of the family is cut, all of them are cut. However, if the Pokemon has a branched evolution, you are allowed to cut said branches, as long as at least one evolution remains.
>You can't cut Pikachu.

Optional Rules:
>Easy Mode: You must fill the following niches; At least one regional rodent, at least one regional early game bird, one early game bug with a middle "Pupa" form, at least two fossil mons, and a single Pseudo-Legendary line.
>Normal Mode: You must have at least two evolutionary lines of Pokemon from each generation.
>Hard Mode: Each starter must come from a different generation.
>Lunatic Mode: Ignore your personal bias and pick the Pokemon you think Gamefreak would want to keep for shilling purposes.