A word of warning -- I’m changing most of your team, as the Pokemon you’ve selected aren’t very viable in OU. If you want to use this team to more success, you should use it in one of the lower tiers.
Samurott
Samurott is in NU, which is a far cry from OU. It isn’t viable at all, and there are better Water types. Gastrodon and Jellicent are two of the better Water types, being quite bulky and able to hit hard specially. Gyarados is an extremely potent physical Water attacker, and I’ll provide sets for all three.
Gastrodon @ Leftovers
Ability: Storm Drain
EVs: 252 HP / 252 Def / 4 SpD
Relaxed Nature
- Earth Power
- Scald
- Toxic / Ice Beam
- Recover
Jellicent @ Leftovers
Ability: Water Absorb
EVs: 252 HP / 4 Def / 252 SpD
Calm Nature
IVs: 0 Atk
- Scald / Shadow Ball / Night Shade
- Recover
- Taunt
- Will-O-Wisp
Gyarados @ Life Orb / Lum Berry
Ability: Moxie
EVs: 252 Atk / 4 Def / 252 Spe
Adamant Nature
- Dragon Dance
- Waterfall
- Bounce / Ice Fang
- Stone Edge / Earthquake
Arcanine
Arcanine is okay, but why settle for okay when you can do better than that? Infernape is far better offensively, and Heatran is clearly superior defensively. Arcanine is just a little too slow, and its unfortunate pure Fire typing leaves it weak to many threats, like Stealth Rock.
Infernape @ Life Orb
Ability: Iron Fist
EVs: 252 Atk / 4 SpD / 252 Spe
Jolly Nature
- Flare Blitz
- Close Combat
- Mach Punch / U-turn
- Thunder Punch
Heatran @ Leftovers
Ability: Flash Fire
EVs: 252 HP / 4 SpA / 252 SpD
Calm Nature
IVs: 0 Atk
- Magma Storm
- Stealth Rock
- Toxic
- Earth Power / Taunt
Braviary
Don’t use it, plain and simple. Like Samurott, it’s in NU, meaning it’s outclassed. While it works very well in the lower tiers, even up to UU, it’s simply too slow and too frail to serve much use on an OU team. Try Landorus-Therian instead, as it has Intimidate, decent defensives, and a sky-high attack stat. It has boosting moves to be a good attacker, or it can even serve the role of a pivot.
Landorus-Therian @ Choice Scarf
Ability: Intimidate
EVs: 4 HP / 252 Atk / 252 Spe
Naive Nature
- Earthquake
- U-turn
- Stone Edge
- Superpower
Scrafty
While Scrafty isn’t the best in Gen 5 OU, it does work. It’s outclassed by things like Conkeldurr and Terrakion, but I’ll try to stay true to your original team and use Scrafty. Let’s appraise your set.
- TwistedSpoon is a bad item competitively, and you’re better suited to using something like a Life Orb to boost offensive capabilities.
- Brick Break is outclassed by Hi Jump Kick and Drain Punch, as the former has a higher damage output, while the other recovers HP.
- Not having Dragon Dance on this thing automatically makes it not worth considering -- in other words, put Dragon Dance on it at once.
- Rock Slide is too weak. Use Stone Edge or Thunder Punch for your Flying weakness, or Ice Punch to take out threats like Landorus while also covering your Flying weakness.
- Naughty is not a good Nature. Use Jolly for a Speed boost, or Adamant for a damage boost.
Here’s a revised set:
Scrafty @ Life Orb
Ability: Moxie
EVs: 4 HP / 252 Atk / 252 Spe
Jolly Nature
- Dragon Dance
- Drain Punch / Hi Jump Kick
- Crunch
- Stone Edge / Thunder Punch / Ice Punch
Flygon
Why use Flygon when Garchomp exists? Garchomp is OU, Flygon is UU, and Garchomp outclasses Flygon in almost every way. It’s a very prominent threat, and a good member for any team.
Garchomp @ Lum Berry
Ability: Rough Skin
EVs: 252 Atk / 4 SpA / 252 Spe
Naive Nature
- Swords Dance
- Outrage / Dragon Claw
- Earthquake
- Fire Blast / Aqua Tail
Galvantula
Nope. This thing is in RU. Don’t use it in OU. Bug types as a whole aren’t very good in OU, with exceptions being Volcarona, Scizor, and Forretress. Scizor and Forretress are not special attackers, and Volcarona leaves you with another Fire type, not good when hazards and Water types are so prevalent. How about using Thundurus-Therian instead? It has Volt Absorb, it’s decently fast (though it’s still outsped by some threats), and it has an amazing Special Attack.
Thundurus-Therian @ Life Orb
Ability: Volt Absorb
EVs: 4 Def / 252 SpA / 252 Spe
Modest Nature
- Agility
- Thunderbolt
- Hidden Power Ice
- Grass Knot / Focus Blast
I took a few of Smogon’s sets, as I’m not the best at making old-gen sets. I apologize for changing so much of your team, but it’ll make it more viable in OU. Your current team would be better suited to something like UU, after heavy changes are made to the sets, and maybe some of the lower-tiered mons are dumped. Hope I helped, and good luck in competitive!