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Aggron, The The Iron Armor Pokemon..
Type: Steel/Rock

Height: 2.01m
Weight: 360.0kg

Ability: Rock Head
Evolution Chain: -------Lv. 32-------> -------Lv. 42------->

Location in Games:

Ruby/Sapphire: Evolve Lairon
FireRed/LeafGreed: Not Avalible
Colossem: Not Avalible
Emerald: Evolve Lairon

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Battle Strategies:

Battle with Aggron:

Holding: Choise Band
-Earthquake
-Iron Tail
-Rock Slide
-Double-Edge

Simple, these attacks are strong and cover some of it's weaknesses. And Double-Edge gets no re-coil due to Rock Head, so this would do great.

Battle Against Aggron:

Aggron has good Defence, but lower SP.DEF, so i suggest a volley water attack.

Contest Strategy:

Holding: Yellow Scarf
-Sandstorm
-Mud-Slap
-Tackle
-Headbutt

Do this, and you will have few problemes.
1: Sandstorm 
2: Mud-slap
3: Tackle
4: Headbutt
5: Sandstorm

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