Red/Blue
----------------
1: 14
2: 21
3: 24
4: 29
5: 43
6: 43
7: 47
8: 50
Champion:  65

Yellow
----------------
1: 12
2: 21
3: 28
4: 32
5: 50
6: 50
7: 54
8: 55
Champion: 65

Gold/Silver
----------------
1: 9
2: 16
3: 20
4: 25
5: 30
6: 35
7: 31
8: 40
Champion: 50
Red: 81

Crystal
----------------
1: 9
2: 15
3: 20
4: 25
5: 30
6: 35
7: 31
8: 40
Champion: 50
Red: 81

Ruby/Sapphire
----------------
1: 15
2: 18
3: 23
4: 28
5: 31
6: 34
7: 42
8: 43
Champion: 58

Emerald
----------------
1: 15
2: 19
3: 24
4: 29
5: 31
6: 33
7: 42
8: 46
Champion: 58
Champion in Meteor Falls: Level 78

FireRed/LeafGreen
----------------
1: 14
2: 21
3: 24
4: 29
5: 43
6: 43
7: 47
8: 50
Champion: 63
Champion Rematch: 75

Diamond/Pearl
----------------
1: Level 14
2: Level 22
3: Level 30
4: Level 30
5: Level 36
6: Level 39
7: Level 42
8: Level 49
Champion: Level 66

Platinum
----------------
1: Level 14
2: Level 22
3: Level 26
4: Level 32
5: Level 37
6: Level 41
7: Level 44
8: Level 50
Champion: Level 62
Champion Rematch: Level 78

HeartGold/SoulSilver
----------------
1: Level 13
2: Level 17
3: Level 19
4: Level 25
5: Level 31
6: Level 35
7: Level 34
8: Level 41
Champion: 50
Champion Rematch: 75
Red: 88

Here are the level limits for the Generation 5 games:
Pokémon Black/White

Gym Leaders

Gym #1: Level 14

Gym #2: Level 20

Gym #3: Level 23

Gym #4: Level 27

Gym #5: Level 31

Gym #6: Level 35

Gym #7: Level 39

Gym #8: Level 43

Pokémon League

Elite Four: Level 50

Inside Team Plasma's castle

Battle 1: Level 52

Battle 2: Level 54

Rematch

Elite Four: Level 73

Champion: Level 77

Undella Town

Battle with Strong Trainer: Level 77
Pokémon Black/White 2

Gym Leaders

Gym #1: Level 13

Gym #2: Level 18

Gym #3: Level 24

Gym #4: Level 30

Gym #5: Level 33

Gym #6: Level 39

Gym #7: Level 48

Gym #8: Level 51

Pokémon League

Elite Four: Level 58

Champion: Level 59

Rematch

Elite Four: Level 74

Champion: Level 78

Here are the level limits for the Generation 6 games:
Pokémon X/Y

Gym Leaders

Gym Leader #1: Level 12

Gym Leader #2: Level 25

Gym Leader #3: Level 32

Gym Leader #4: Level 34

Gym Leader #5: Level 37

Gym Leader #6: Level 42

Gym Leader #7: Level 48

Gym Leader #8: Level 59

Pokémon League

Elite Four: Level 65

Champion: Level 68

Rematch

Elite Four: Level 74

Champion: Level 78
Pokémon Omega Ruby/Alpha Sapphire

Gym Leaders

Gym #1: Level 14

Gym #2: Level 16

Gym # 3: Level 21

Gym #4: Level 28

Gym #5: Level 30

Gym #6: Level 35

Gym #7: Level 45

Gym #8: Level 46

Pokémon League

Elite Four #1: Level 52

Elite Four #2: Level 53

Elite Four #3: Level 54

Elite Four #4: Level 55

Champion: Level 59

Rematches

Elite Four #1: Level 72

Elite Four #2: Level 73

Elite Four #3: Level 74

Elite Four #4: Level 75

Champion: Level 79

Here are the level limits for the Generation 7 games:
Pokémon Sun/Moon

Trials and Captains

Trial Captain #1 Illima: Level 10

Normal Trial: Level 12

Kahuna Hala: Level 15

Water Trial: Level 20

Trial Captain #2 Lana: Level 27

Fire Trial: Level 22

Trial Captain #3 Kiawe: Level 27

Grass Trial: Level 24

Trial Captain #4 - Mallow: Level 27

Kahuna Olivia: Level 27

Electric Trial: Level 29

Guzma: Level 31

Ghost Trial: Level 33

Second battle against Guzma: Level 37

Kahuna Nanu: Level 39

Third battle against Guzma: Level 41

Lusamine: Level 41

Kahuna Hapu: Level 48

Dragon Trial: Level 45

Second battle against Lusamine: Level 50

Captains in the Post Game

Trial Captain #5 Sophocles: Level 61

Trial Captain #7 Mina: Level 61

Pokémon League

Elite Four: Level 55 Champion: Level 58

Rematch

Elite Four: Lvl 63 Champion: Depending on Trainer, either Level 59, Level 61, Level 63, Level 65
Pokémon Ultra Moon

Trials

Normal Trial: Level 12

Water Trial: Level 20

Fire Trial: Level 22

Grass Trial: Level 24

Electric Trial: Level 33

Ghost Trial: Level 35

Dragon Trial: Level 49

Fairy Trial: Level 55

Ilima's Trial: Level 60

Captains in the Post Game

Trial Captain #1 Ilima: Level 60

Trial Captain #2 Lana: Level 60

Trial Captain #3 Kiawe: Level 60

Trial Captain #4 Mallow: Level 60

Trial Captain #5 Sophocles: Level 67

Trial Captain #6 Acerola:Level 66

Pokémon League

Elite Four: Level 57 Champion: Level 60

Rematch

Elite Four: Level 66 Champion: Depending on Trainer, either Level 66, Level 67, Level 68, Level 69, Level 70

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