This is the second team I've ever made, and this is my second RMT. I'm new to competitive battling, and have only been playing for a few weeks. All the help I can get to improve my team is appreciated.
The team I made is focused around sweeping with Aggron.
All changes to this team are in bold.
KABUTOPS
Kabutops @ Lum Berry
Adamant
Swift Swim
252 Atk/252 Spe/4 HP
~Stealth Rock
~Stone Edge
~Aqua Jet
~Rapid Spin
Kabutops is my lead. His job is to immediately set up stealth rock, and to do as much damage as possible. After setting up stealth rock, Kabutops can attack or switch out to be used later as a sweeper or rapid spinner. Kabutops can stand up to common leads like Ambipom and Uxie. Kabutops takes little damage from Ambipom, and Kabutop's Lum Berry allows it to set up stealth rocks on the first turn even if it is statused. Kabutops can also rapid spin the opponent's entry hazards, which can hurt my team. Stone Edge is used for flying and fire types, and Aqua Jet is a good priority move for Fire, Rock, and Ground types.
252 attack EVs are used because Kabutops is being used physical attacker. 252 speed EVs allows Kabutops to outspeed as much pokemon as possible.
AGGRON
Aggron @ Life Orb
Adamant
Rock Head
252 Atk/252 Spe/ 4 Def
~Head Smash
~Aqua Tail
~Earthquake
~Rock Polish
Aggron is what I built this team around. He is my main sweeper. I'm using a rock polish Aggron set because the speed boost rock polish gives makes Aggron a much better pokemon. Thanks to Aggron's typing and defense, my opponent will usually switch out their pokemon, giving me a free turn to use Rock Polish. Head Smash is Aggron's main move. Thanks to Aggron's ability, Rock Head, Head Smash has no recoil damage. Aqua Tail is for Rock and Ground types that try to counter Aggron. With Rock Polish, Aggron outspeeds them and OHKOs them with Aqua Tail. Earthquake is for finishing off a pokemon so I don't have to use a move with bad accuracy, as well as a way to deal with Registeel.
252 Attack and Speed EVs allow Aggron to hit harder and make sure it OHKOs Aggron's counters, and makes sure that it outspeeds them.
BLAZIKEN
Blaziken @ Expert Belt
Rash
Blaze
192 Atk/252 SpA/64 Spe
~Fire Blast
~Flare Blitz
~Hidden Power Grass
~Superpower
Blaziken is my early-game sweeper. It can easily break walls, which can give my team trouble. Blaziken's main attack is Fire Blast. It does a lot of damage to almost any pokemon Blaziken goes up against. Flare Blitz is a physical Fire attack to be used if I don't want to deal with the stat drop that Superpower gives. Hidden Power Grass is for Water and Ground types that counter Blaziken, such as Milotic and Donphan. Superpower is Blaziken's fighting STAB that is for Rock, Dark types. Superpower can also be used to finish off a pokemon if they resist Fire Blast. I chose Expert Belt over Life Orb because Blaziken lives longer with an Expert Belt. Even without the boost of a Life Orb, Blaziken still does a lot of damage.
192 Attack EVs are used for making Superpower and Flare Blitz do more damage. 252 Special Attack EVs are used for Fire Blast, Its main move, and HP Grass. 64 Speed EVs are used to outspeed other pokemon without an Agility boost.
ROTOM
Rotom @ Choice Scarf
Modest
Levitate
252 SpA/252 Spe/4 HP
~Thunderbolt
~Shadow Ball
~Hidden Power Ice
~Trick
Rotom makes a great partner with Aggron because Rotom can switch into anything threatening Aggron. Thinderbolt is Rotom's main attack. It is used against water types that threaten Aggron, as well as anything that doesn't resist it. Shadow Ball is for Ghost and Psychic types, and anything else that resists Thunderbolt. Hidden Power Ice can OHKO Ground, Rock, and Grass types that Aggron can't handle, like Torterra. Rotom can trick its Choice Scarf onto a sweeper, but this usually isn't needed.
252 Special Attack EVs are used because Rotom is a special attacker, and 252 Speed EVs are used for outspeeding as many pokemon as possible.
AZUMARILL
Azumarill @ Choice Band
Adamant
Huge Power
252 Atk/240 HP/16 Spe
~Waterfall
~Aqua Jet
~Double Edge
~Ice Punch
Azumarill is a powerful bulky pokemon that can switch into many attacks. Thanks to Huge Power, Azumarill becomes a good physical attacker. It can switch into Moltres, which is a threat to my team, and easily OHKO it with Aqua Jet. With Stealth Rock up, Moltres won't have a chance to survive even if it switches out. Waterfall is Azumarill's main move, but Aqua Jet is used when it needs to go first. Double Edge can be used against anything that resists Water. Ice Punch is for hitting Ground, Rock, Grass, and Flying types that threaten the rest of my team.
252 Attack EVs are used because the Azumarill set uses physical attacks, and 240 HP EVs are used to make Azumarill more bulky.
LEAFEON
Leafeon @ Leftovers
Impish
Leaf Gaurd
252 HP/252 Def/4 Spe
~Wish
~Leaf Blade
~Yawn
~Protect
Leafeon provides support for my team, as well as scouting. Leafeon makes a good physical tank thanks to its high defense and high attack and speed. Wish offers healing for the rest of my team, and also allows Leafeon to heal. Leaf Blade can be used against Ground, Rock, and Water types that give my team trouble, such as Milotic. Yawn is used to force a switch, which is useful for ruining my opponent's attempt to sweep. Protect is used to scout and to heal Leafeon when it uses Wish for itself.
252 HP EVs are used to help with Leafeon's bad HP stat, and 252 Defense EVs are used to increase Leafeon's great Defense stat.
The team I made is focused around sweeping with Aggron.
All changes to this team are in bold.
KABUTOPS

Kabutops @ Lum Berry
Adamant
Swift Swim
252 Atk/252 Spe/4 HP
~Stealth Rock
~Stone Edge
~Aqua Jet
~Rapid Spin
Kabutops is my lead. His job is to immediately set up stealth rock, and to do as much damage as possible. After setting up stealth rock, Kabutops can attack or switch out to be used later as a sweeper or rapid spinner. Kabutops can stand up to common leads like Ambipom and Uxie. Kabutops takes little damage from Ambipom, and Kabutop's Lum Berry allows it to set up stealth rocks on the first turn even if it is statused. Kabutops can also rapid spin the opponent's entry hazards, which can hurt my team. Stone Edge is used for flying and fire types, and Aqua Jet is a good priority move for Fire, Rock, and Ground types.
252 attack EVs are used because Kabutops is being used physical attacker. 252 speed EVs allows Kabutops to outspeed as much pokemon as possible.
AGGRON

Aggron @ Life Orb
Adamant
Rock Head
252 Atk/252 Spe/ 4 Def
~Head Smash
~Aqua Tail
~Earthquake
~Rock Polish
Aggron is what I built this team around. He is my main sweeper. I'm using a rock polish Aggron set because the speed boost rock polish gives makes Aggron a much better pokemon. Thanks to Aggron's typing and defense, my opponent will usually switch out their pokemon, giving me a free turn to use Rock Polish. Head Smash is Aggron's main move. Thanks to Aggron's ability, Rock Head, Head Smash has no recoil damage. Aqua Tail is for Rock and Ground types that try to counter Aggron. With Rock Polish, Aggron outspeeds them and OHKOs them with Aqua Tail. Earthquake is for finishing off a pokemon so I don't have to use a move with bad accuracy, as well as a way to deal with Registeel.
252 Attack and Speed EVs allow Aggron to hit harder and make sure it OHKOs Aggron's counters, and makes sure that it outspeeds them.
BLAZIKEN

Blaziken @ Expert Belt
Rash
Blaze
192 Atk/252 SpA/64 Spe
~Fire Blast
~Flare Blitz
~Hidden Power Grass
~Superpower
Blaziken is my early-game sweeper. It can easily break walls, which can give my team trouble. Blaziken's main attack is Fire Blast. It does a lot of damage to almost any pokemon Blaziken goes up against. Flare Blitz is a physical Fire attack to be used if I don't want to deal with the stat drop that Superpower gives. Hidden Power Grass is for Water and Ground types that counter Blaziken, such as Milotic and Donphan. Superpower is Blaziken's fighting STAB that is for Rock, Dark types. Superpower can also be used to finish off a pokemon if they resist Fire Blast. I chose Expert Belt over Life Orb because Blaziken lives longer with an Expert Belt. Even without the boost of a Life Orb, Blaziken still does a lot of damage.
192 Attack EVs are used for making Superpower and Flare Blitz do more damage. 252 Special Attack EVs are used for Fire Blast, Its main move, and HP Grass. 64 Speed EVs are used to outspeed other pokemon without an Agility boost.
ROTOM

Rotom @ Choice Scarf
Modest
Levitate
252 SpA/252 Spe/4 HP
~Thunderbolt
~Shadow Ball
~Hidden Power Ice
~Trick
Rotom makes a great partner with Aggron because Rotom can switch into anything threatening Aggron. Thinderbolt is Rotom's main attack. It is used against water types that threaten Aggron, as well as anything that doesn't resist it. Shadow Ball is for Ghost and Psychic types, and anything else that resists Thunderbolt. Hidden Power Ice can OHKO Ground, Rock, and Grass types that Aggron can't handle, like Torterra. Rotom can trick its Choice Scarf onto a sweeper, but this usually isn't needed.
252 Special Attack EVs are used because Rotom is a special attacker, and 252 Speed EVs are used for outspeeding as many pokemon as possible.
AZUMARILL

Azumarill @ Choice Band
Adamant
Huge Power
252 Atk/240 HP/16 Spe
~Waterfall
~Aqua Jet
~Double Edge
~Ice Punch
Azumarill is a powerful bulky pokemon that can switch into many attacks. Thanks to Huge Power, Azumarill becomes a good physical attacker. It can switch into Moltres, which is a threat to my team, and easily OHKO it with Aqua Jet. With Stealth Rock up, Moltres won't have a chance to survive even if it switches out. Waterfall is Azumarill's main move, but Aqua Jet is used when it needs to go first. Double Edge can be used against anything that resists Water. Ice Punch is for hitting Ground, Rock, Grass, and Flying types that threaten the rest of my team.
252 Attack EVs are used because the Azumarill set uses physical attacks, and 240 HP EVs are used to make Azumarill more bulky.
LEAFEON

Leafeon @ Leftovers
Impish
Leaf Gaurd
252 HP/252 Def/4 Spe
~Wish
~Leaf Blade
~Yawn
~Protect
Leafeon provides support for my team, as well as scouting. Leafeon makes a good physical tank thanks to its high defense and high attack and speed. Wish offers healing for the rest of my team, and also allows Leafeon to heal. Leaf Blade can be used against Ground, Rock, and Water types that give my team trouble, such as Milotic. Yawn is used to force a switch, which is useful for ruining my opponent's attempt to sweep. Protect is used to scout and to heal Leafeon when it uses Wish for itself.
252 HP EVs are used to help with Leafeon's bad HP stat, and 252 Defense EVs are used to increase Leafeon's great Defense stat.