id,identifier,generation_id,order
1,red-blue,1,1
2,yellow,1,2
3,gold-silver,2,3
4,crystal,2,4
5,ruby-sapphire,3,5
6,emerald,3,6
7,firered-leafgreen,3,9
8,diamond-pearl,4,10
9,platinum,4,11
10,heartgold-soulsilver,4,12
11,black-white,5,13
12,colosseum,3,7
13,xd,3,8
14,black-2-white-2,5,14
15,x-y,6,15
16,omega-ruby-alpha-sapphire,6,16
17,sun-moon,7,17
18,ultra-sun-ultra-moon,7,18
19,lets-go-pikachu-lets-go-eevee,7,19
20,sword-shield,8,20