The game files store 101 as a sentinel for moves that cannot miss, so this move never misses.
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Pokemon that learn Amnesia

Appletun
Grass / Dragon · 485

Audino
Normal · 445

Mega Audino
Normal / Fairy · 545

Azumarill
Water / Fairy · 420

Camerupt
Fire / Ground · 460

Mega Camerupt
Fire / Ground · 560

Castform (Normal)
Normal · 420

Castform (Rainy Form)
Water · 420

Castform (Snowy Form)
Ice · 420

Castform (Sunny Form)
Fire · 420

Clefable
Fairy · 483

Mega Clefable
Fairy / Flying · 583

Crabominable
Fighting / Ice · 478

Mega Crabominable
Fighting / Ice · 578

Drampa
Normal / Dragon · 485

Mega Drampa
Normal / Dragon · 585

Farigiraf
Normal / Psychic · 520

Garbodor
Poison · 474

Hippowdon
Ground · 525

Mamoswine
Ice / Ground · 530

Musharna
Psychic · 487

Politoed
Water · 500

Primarina
Water / Fairy · 530

Runerigus
Ground / Ghost · 483

Scrafty
Dark / Fighting · 488

Mega Scrafty
Dark / Fighting · 588

Simisear
Fire · 498

Slowbro
Water / Psychic · 490

Galarian Slowbro
Poison / Psychic · 490

Mega Slowbro
Water / Psychic · 590

Slowking
Water / Psychic · 490

Galarian Slowking
Poison / Psychic · 490

Slurpuff
Fairy · 480

Snorlax
Normal · 540

Swampert
Water / Ground · 535

Mega Swampert
Water / Ground · 635

Torkoal
Fire · 470

Torterra
Grass / Ground · 525

Venusaur
Grass / Poison · 525

Mega Venusaur
Grass / Poison · 625

Volcarona
Bug / Fire · 550
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