As far as pseudo-legendary Pokemon go, Goodra is a bit of an odd duck. One being that it is a pure Dragon type, and the other that it's stats seem to favor a bulkier build rather than a powerhouse sweeper like its other brethren. Despite not quite fitting in within that crowd, Goodra is still a very versatile choice for team building complete with three excellent abilities, a wide offensive movepool, and even a few neat tricks that keeps your opponents guessing as to how Goodra will be used, provided you are able to accommodate its specific needs and are able to play into its strengths.
Wall of Slime
Ability: Sap Sipper/Gooey
Item: Assault Vest
Nature: Bold
EVs: (HP 252) (Def 252) (SpDef 4)
Moves:
Dragon Pulse/Draco Meteor
Fire Blast
Sludge Bomb
Thunderbolt/Surf
Set Details:
A bulky tank set that capitolizes on Goodra's 150 base special defense while buffing its physical defense with the proper nature and EVs. This set can tank special hit like a freaking Chansey and can still hit back thanks to its wide offense options. Dragon Pulse is the default neutral STAB but Draco Meteor is also an option if you are quick to switch, Fire Blast covers Steel types that resist your Dragon STAB and Sludge Bomb covers you against Fairy types that are outright immune. The last slot is a matter of coverage preference with Thunderbolt hitting the copious amounts of Water and Flying types (Gyarados especially), and Surf drowns out the Fire, Ground and Rock types. Ability choice is also up to preference as an immunity to Grass attacks and Sleep Powder is always welcome, but Gooey is handy to have around also since faster direct attackers will be punished and then subsequent outsped by Goodra which still sits at a comfortable base 80 speed.
Keeping Yourself Well-Hydrated
Ability: Hydration
Item: Leftovers
Nature: Bold
EVs: (HP 252) (Def 252) (SpDef 4)
Moves:
Rain Dance
Rest
Dragon Pulse
Muddy Water/Surf
Set Details:
Access to excellent defensive stats and Hydration as an ability opens the door to a Hydration Rest strategy that keeps Goodra's health in the green while whittling away the opponent. Set up Rain Dance and while rain is active it allows you to instantly wake up from Rest after using it, allowing you to recover 100% of your health and shedding off any burns, paralysis, poisoning. Dragon Pulse is your most reliable STAB and a Water attack has good neutral coverage with your STAB and also benefits from the power boost granted by the rain. Muddy Water may be less accurate than Surf, but the high chance of accuracy drop can force your opponent to switch or risk missing on subsequent moves against Goodra, but if the accuracy still turns you off then Surf is still a safe bet. Lefteovers provides additional recovery and EVs/Nature is poured into HP and Defense since Goodra already has Special Defense in spades.
Escargoo
Ability: Sap Sipper/Hydration
Item: Leftovers
Nature: Impish
EVs: (HP 252) (Def 252) (SpDef 4)
Moves:
Curse
Outrage
Earthquake
Iron Tail/Power Whip/Fire Punch
Set Details:
A physical variant on Goodra since Goodra has an attack stat that is nearly as high as its special, not to mention it has access to the boosting move Curse to make Goodra not only stronger, but bulkier too at the cost of speed. Outrage is unfortunately the only physcial STAB goodra has access to, but as long as you are mindful of any Fairy types in the opponent's team and temper the confusion risk afterward you should be fine. Earthquake has almost prefect coverage with Outrage, so the last slot is a matter of filling in the holes in your coverage or just surprising the opposition not expecting your final attack slot. Iron Tail punishes the Fairy types but has shaky accuracy, Power Whip whips the Water/Ground types ho think they can come in and set up on you, and Fire Punch surprises the likes of Bronzong, Ferrothorn, and Scizor who think they can take whatever Goodra dishes out. Leftovers provides additional bulk and the Nature/EVs keep Goodra as resilient as physically possible. Ability choice typically goes to Sap Sipper since the added immunity to Grass attacks and Grass status is welcome (Not to mention it increases Goodra's attack even further), but Hydration is a worth a mention if you have rain support and don't want a stray burn or badly poison to ruin your game.
So Goodra has a lot to offer to the Pokemon World in the form of competitive usage, and not just in the form of rule 34 lewds...
Seriously, DO NOT Google Goodra lewds. You WILL regret it.