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 Yawn
Audino
Normal · 445
Mega Audino
Normal / Fairy · 545
Beartic
Ice · 505
Blastoise
Water · 530
Mega Blastoise
Water · 630
Camerupt
Fire / Ground · 460
Mega Camerupt
Fire / Ground · 560
Chimecho
Psychic · 455
Mega Chimecho
Psychic / Steel · 555
Emboar
Fire / Fighting · 528
Mega Emboar
Fire / Fighting · 628
Empoleon
Water / Steel · 530
Espeon
Psychic · 525
Flareon
Fire · 525
Glaceon
Ice · 525
Hippowdon
Ground · 525
Houndstone
Ghost · 488
Hydrapple
Grass / Dragon · 540
Jolteon
Electric · 525
Leafeon
Grass · 525
Liepard
Dark · 446
Meowstic (Female)
Psychic · 466
Meowstic (Male)
Psychic · 466
Mega Meowstic (Male)
Psychic · 566
Mega Meowstic (Female)
Psychic · 566
Musharna
Psychic · 487
Oranguru
Normal / Psychic · 490
Pyroar
Fire / Normal · 507
Mega Pyroar
Fire / Normal · 607
Simisear
Fire · 498
Skeledirge
Fire / Ghost · 530
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
Stunfisk
Ground / Electric · 471
Galarian Stunfisk
Ground / Steel · 471
Swampert
Water / Ground · 535
Mega Swampert
Water / Ground · 635
Sylveon
Fairy · 525
Torkoal
Fire · 470
Umbreon
Dark · 525
Vaporeon
Water · 525
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