invalid team?

Politoed @ Damp Rock
Ability: Drizzle
EVs: 252 Def / 252 HP / 4 SAtk
Bold Nature
- Scald
- Perish Song
- Toxic
- Protect

Tentacruel @ Black Sludge
Ability: Rain Dish
EVs: 244 Def / 248 HP / 16 Spd
Bold Nature
- Scald
- Rapid Spin
- Substitute
- Toxic Spikes

Gastrodon @ Leftovers
Ability: Storm Drain
EVs: 252 Def / 252 HP / 4 SAtk
Bold Nature
- Scald
- Recover
- Earth Power
- Toxic

Cloyster @ Focus Sash
Ability: Skill Link
EVs: 252 Spd / 252 Atk / 4 HP
Jolly Nature
- Icicle Spear
- Ice Shard
- Shell Smash
- Rock Blast

Starmie @ Choice Specs
Ability: Natural Cure
EVs: 252 Spd / 252 SAtk / 4 SDef
Timid Nature
- Surf
- Thunderbolt
- Psyshock
- Ice Beam

Gyarados @ Gyaradosite
Ability: Intimidate
EVs: 252 Spd / 252 Atk / 4 HP
Jolly Nature
- Substitute
- Waterfall
- Dragon Dance
- Earthquake

How is it invalid?