Ice Beam is redundant with Goodra's Dragon STAB. Don't bother with it. Goodra is also currently walled by Heatran:
-Draco Meteor
-Fire Blast
-Thunderbolt/Earthquake
-Dragon Tail/Earthquake
Nature: Quiet/Sassy
EVs: 248 HP/252 SAtk/8 SDef
Item: Assault Vest
Ability: Gooey/Sap Sipper
or
-Draco Meteor
-Fire Blast
-Thunderbolt
-Focus Blast
Nature: Modest
EVs: 248 HP/252 SAtk/8 SDef
Item: Choice Specs
Ability: Gooey/Sap Sipper
If you're looking for alternative items besides Leftovers for Ferrothorn, use Rocky Helmet. It works well in tandem with Iron Barbs:
-Leech Seed
-Protect
-Gyro Ball/Thunder Wave
-Stealth Rock/Spikes/Power Whip
Nature: Relaxed/Impish
EVs: 248 HP/252 Def/8 SDef
Item: Leftovers/Rocky Helmet
Ability: Iron Barbs
or
-Stealth Rock/Spikes
-Leech Seed
-Gyro Ball/Thunder Wave
-Power Whip/Protect
Nature: Relaxed
EVs: 248 HP/52 Def/208 SDef
Item: Leftovers/Rocky Helmet
Ability: Iron Barbs
Hurricane is only good on rain teams; it's inaccurate outside of that. While I still think offensive Quiver Dance Volcarona is viable, defensive Quiver Dance may be better because it lets Volcarona heal off the damage it takes from Stealth Rock:
-Quiver Dance
-Fiery Dance
-Bug Buzz
-Roost
Nature: Bold
EVs: 248 HP/192 Def/68 Spe
Item: Leftovers
Ability: Flame Body
If you still want to use offensive Volcarona, you're better off using a better coverage move than Hurricane because it's horribly inaccurate:
-Quiver Dance
-Fire Blast/Fiery Dance
-Bug Buzz
-Hidden Power (Rock/Ground)/Psychic
Nature: Timid/Modest
EVs: 252 SAtk/4 SDef/252 Spe
Item: Life Orb/Lum Berry
Ability: Flame Body
I don't like having Golurk on the team at all. It's slow, not that bulky and it has common weaknesses that are easily exploited. I think that Aegislash is a better alternative, as while it also has its fair share of common weaknesses, it has the bulk to take those hits:
-Shadow Ball
-Shadow Sneak
-Pursuit/Iron Head/Sacred Sword
-King's Shield
Nature: Quiet
EVs: 244 HP/252 SAtk/12 Spe
Item: Leftovers
or
-Substitute
-Toxic
-King's Shield
-Shadow Ball
Nature: Modest
EVs: 244 HP/252 SAtk/12 Spe
Item: Leftovers
or
-Shadow Ball
-Shadow Sneak
-Flash Cannon/Sacred Sword
-Sacred Sword/Pursuit
Nature: Hasty/Naive
EVs: 4 Atk/252 SAtk/252 Spe
Item: Life Orb/Spooky Plate/Spell Tag
or
-Swords Dance
-Shadow Sneak
-Iron Head/Shadow Claw
-Sacred Sword/Head Smash
Nature: Adamant
EVs: 252 Atk/4 SDef/252 Spe
Item: Life Orb
I think that Scizor would make a fine addition in the last slot as a Defogger because while it adds another Fire weakness, it can strike hard on the physical end:
-U-turn
-Bullet Punch/Knock Off
-Defog
-Roost
Nature: Impish
EVs: 248 HP/252 Def/8 SDef
Item: Scizorite
Ability: Technician
In the last slot, you can use another Fire resist like Azumarill:
-Waterfall
-Aqua Jet
-Play Rough
-Superpower/Knock Off
Nature: Adamant
EVs: 164 HP/252 Atk/92 Spe
Item: Choice Band/Splash Plate/Mystic Water
Ability: Huge Power
or
-Belly Drum
-Aqua Jet
-Play Rough
-Waterfall/Superpower
Nature: Jolly
EVs: 4 HP/252 Atk/252 Spe
Item: Sitrus Berry
Ability: Huge Power
or
-Aqua Jet
-Play Rough
-Power-Up Punch
-Waterfall/Knock Off
Nature: Adamant
EVs: 16 HP/252 Atk/240 SDef
Item: Assault Vest
Ability: Huge Power
If you don't want an extra Fire weakness, use Mega Blastoise or Starmie instead:
Mega Blastoise:
-Water Pulse/Scald/Hydro Pump
-Dark Pulse
-Aura Sphere/Ice Beam
-Rapid Spin
Nature: Modest
EVs: 252 HP/252 SAtk/4 SDef
Item: Blastoisinite
Starmie:
-Hydro Pump/Surf
-Ice Beam
-Psyshock/Thunderbolt
-Rapid Spin
Nature: Timid
EVs: 252 SAtk/4 SDef/252 Spe
Item: Life Orb/Leftovers
Ability: Natural Cure
If you opted for either Mega Blastoise or Starmie, Black Kyurem, Conkeldurr, or Dragonite make fine options in the last slot:
Black Kyurem:
-Ice Beam
-Fusion Bolt
-Earth Power
-Substitute/Roost
Nature: Mild/Hasty
EVs: 56 HP/200 SAtk/252 Spe (Substitute) or 4 Atk/252 SAtk/252 Spe (Roost)
Item: Leftovers (Sub)/Life Orb (Roost)
or
-Outrage
-Ice Beam
-Fusion Bolt
-Iron Head/Earth Power/Dragon Claw
Nature: Hasty
EVs: 252 Atk/4 SAtk/252 Spe
Item: Life Orb
or
-Ice Beam
-Dragon Tail
-Fusion Bolt
-Roost
Nature: Hasty
EVs: 248 HP/60 SDef/200 Spe
Item: Leftovers
or
-Outrage
-Ice Beam
-Fusion Bolt
-Iron Head/Dragon Claw
Nature: Lonely
EVs: 252 Atk/4 SAtk/252 Spe
Item: Choice Band
Conkeldurr:
-Drain Punch
-Mach Punch
-Knock Off
-Ice Punch/Stone Edge
Nature: Adamant
EVs: 188 HP/252 Atk/48 SDef/20 Spe or 252 Atk/236 SDef/20 Spe
Item: Assault Vest
Ability: Guts
or
-Bulk Up
-Drain Punch
-Mach Punch
-Knock Off/Stone Edge/Ice Punch
Nature: Adamant
EVs: 252 Atk/4 Def/252 SDef
Item: Leftovers
Ability: Guts
Dragonite:
-Dragon Dance
-Dragon Claw/Outrage
-Extreme Speed
-Earthquake
Nature: Adamant
EVs: 252 Atk/4 SDef/252 Spe
Item: Lum Berry/Weakness Policy
Ability: Multiscale