The Metronome Randomizer mimics the attack "Metronome" in the Pokémon games, choosing a series of random attacks. This script offers three different flavors of metronome--"True Metronome," which adheres to the mechanics of the attack in the main-series games; "All Attacks," which picks any non-Z-move attack; and "All With Z-Moves," which may generate a Z-move, even though Z-moves aren't really the same as ordinary attacks and definitely can't be called by metronome. True Metronome will never select Counter, Mimic, Metronome, Mirror Move, Transform, Struggle, Sketch, Thief, Snore, Protect, Destiny Bond, Detect, Endure, Sleep Talk, Mirror Coat, Focus Punch, Follow Me, Nature Power, Helping Hand, Trick, Assist, Snatch, Covet, Feint, Me First, Copycat, Switcheroo, Chatter, Wide Guard, Rage Powder, After You, Quick Guard, Quash, Bestow, Techno Blast, Relic Song, Secret Sword, Freeze Shock, Ice Burn, Snarl, or V-create. If you are concerned with strict adherence to game mechanics, you should also take into account the fact that Metronome will also never pick any of the user's other three attacks, either, so you may need to re-randomize.
Because the mechanics of metronome haven't yet been extensively explored for Gen VII (and likely won't be for a while), the "True Metronome" setting currently chooses any attack that could be called in the fifth generation and any attack introduced in the sixth or seventh generation, since it's not currently known which of them are actually callable.