Coalossal's main use in Gen 8 Doubles involves his Steam Engine ability.
Coalossal @ Weakness Policy
Level: 50
Ability: Steam Engine
EVs: 76 HP / 252 SpA / 180 Spe
Modest Nature
- Heat Wave
- Meteor Beam
- Solar Beam
- Protect
One of the most used sets involves Gigantamax with Steam Engine and Weakness Policy. Use with another Pokemon that has access to Surf, but won't do much damage, like Weavile. This gives you the ability to instantly get +6 Spe, +2 Atk, and +2 Sp.Atk. This makes Coalossal a threatening weapon in doubles that can sweep teams if used correctly
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