As the Gym Leader of Sootopolis City, Wallace's Ruby/Sapphire team consists of:
Lv.40 Luvdisc (Water)
Lv.40 Sealeo (Ice/Water)
Lv.42 Seaking (Water)
Lv.42 Whiscash (Water/Ground)
Lv.43 Milotic (Water)
They are all water types, with Sealeo and Whiscash having secondary typing of Ice and Ground respectively. None of these Pokemon hold items. Strategy for facing this team is fairly straight forward. I recommend bringing along Electric types, but also making sure to have a Grass type on hand to handle Whiscash, who is immune to Electric types. Obviously, it is highly recommended that you do not bring your Fire, Ground, Water, or Rock types into a Water battle. Beating these Pokemon can be relatively easy if you know how to handle their types, but be for warned that Milotic knows recover, which can pose a problem if not taken down quickly. After defeating Wallace, you will receive. TM 03 (Water Pulse) and the Rain Badge, which will have all Pokemon obey you, and allows you to use the HM Waterfall outside of battle.
As the Hoenn League Champion, Wallace's Emerald team consists of:
Lv.57 Wailord (Water)
Lv.55 Tentacrual (Water/Poison)
Lv.56 Ludicolo (Water/Grass)
Lv.56 Whiscash (Water/Ground)
Lv.56 Gyarados (Water/Flying)
Lv.58 Milotic (Water)
In Pokemon Emerald, Wallace has become the League Champion. Therefore, his Pokemon team now consists of six Pokemon instead of five, and they are a higher level. He also switches things up just a bit, and Luvdisc, Sealeo, and Seaking are no longer used. Milotic is the only Pokemon to hold an item, a Sitrus Berry that restores 30HP when used. This team, minus Milotic and Wailord all have secondary typing, so things can be a bit trickier. Your Electric types will still work well on this team, except when dealing with Ludicolo, and Whiscash. Whiscash sports a weakness to Grass type however, and Ludicolo can be brought down with either Flying, Poison, or Bug.
Like before, do not bring your Fire, Ground, Water, Rock, or Steel types to this battle. They will not fare well. Tentacruel and Gyarados are both resistant to a bunch of different typings, so watch out for that. Electric types will work well against them, and deal x2 damage against Gyarados. One thing I recommend when fighting Champion Wallace is to come prepared for poisonings. Both Milotic and Tentacruel know Toxic, and will be quick to poison your Pokemon. You also have to be careful when using Grass types against Wailord, Tentacruel, and Milotic, as they all have Ice attacks that can damage you very quickly.
As the Gym Leader of Sootopolis City, Wallace's Omega Ruby/Alpha Sapphire team consists of:
Lv.44 Luvdisc (Water)
Lv.44 Whiscash (Water/Ground)
Lv.44 Sealeo (Ice/Water)
Lv.44 Seaking (Water)
Lv.46 Milotic (Water)
Wallace uses the same team for Omega Ruby & Alpha Sapphire that he used in the original Ruby & Sapphire. The only differences are their levels, and movesets. Your game plan for the most part is going to be very similar to Ruby and Sapphire. Electric types, and Grass types are going to be your friend. But keep in mind that Electric attacks do not work on Whiscash, and that Sealeo and Milotic know ice type moves that can wear down your Grass types quickly. None of these Pokemon hold items. Luvdisc has also been enhanced with some Fairy type moves, so be aware of that. After defeating Wallace, you will receive the Rain badge, and the HM Waterfall.
Wallace brings back his Emerald team for the Delta Episode. Wallace's team consists of:
Lv.55 Wailord (Water)
Lv.55 Tentacrual (Water/Poison)
Lv.55 Ludicolo (Water/Grass)
Lv.55 Whiscash (Water/Ground)
Lv.55 Gyarados (Water/Flying)
Lv.57 Milotic (Water)
The levels are actually lower than they were in Emerald, however. I recommend taking a look at the recommendations for Emerald, as the battle experience will be very much the same, if not identical.
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