Shell Armor according to type distribution

Psychic:

1. Mega Slowbro

Fire:

1. Turtonator
2. Torkoal

Ice:

1. Cloyster
2. Lapras

Grass:

1. Turtwig
2. Grotle
3. Torterra

Ground:

1. Torterra

Rock:

1. Omanyte
2. Omastar
3. Dwebble
4. Crustle
5. Drednaw

Steel:

1. Escavalier

Bug:

1. Dwebble
2. Crustle
3. Escavalier
4. Shelmet

Dark:

1. Crawdaunt

Water:

1. Mega Slowbro  
2. Shellder
3. Cloyster
4. Krabby
5. Kingler
6. Lapras
7. Omanyte
8. Omastar
9. Corphish
10. Crawdaunt
11. Clamperl
12. Oshawott
13. Dewott
14. Samurott
15. Chewtle
16. Drednaw

Edit (01.01.2020): Added Sword and Shield additions.