Gen 3 Doubles OU
Dewgong @ Leftovers
Ability: Thick Fat
EVs: 248 HP / 60 Def / 16 SpD / 184 Spe
Calm Nature
- Fake Out
- Encore
- Icy Wind
- Protect
Dewgong is... surprisingly good in this format. Fake Out flinches an opponent, preventing their move and allowing Dewgong's ally to attack or set up more safely. Encore can be used to lock an opponent into an unfavourable move, and in Gen 3, this effect can last up to 6 turns. Icy Wind provides a form of speed control for your team, lowering both of the opposing Pokémon's speed by one stage. Protect allows Dewgong to block attacks for a turn while it's all can still attack. Leftovers gives Dewgong recovery, increasing it's longevity (normally I'd suggest Sitrus Berry for healing in doubles, but Sitrus Berry only heals 30 HP in Gen 3).
184 speed EVs allows Dewgong to outspeed 252 speed Adamant Tyranitar, as well as max speed base 100s after an Icy Wind. The HP and Sp. Def EVs allow Dewgong to survive a Thunderbolt from max SpA Zapdos after 1 layer of Spikes damage. The rest of the EVs are in defence.