0706 Goodra

Both of Goodra's fast moves provide decent energy generation and are very easy to use thanks to their fast animations. Dragon Breath is the stronger choice, benefiting from STAB and also being stronger stat-wise. 

Power Whip is a strong Grass-type charge move that costs a moderate amount of energy, and provides useful coverage against common Water-types. Muddy Water is quite poor, but is the cheapest charge move energy-wise and allows Goodra to bait shields more often. Draco Meteor is powerful with STAB, and though it debuffs the user harshly, the threat of its massive damage is not to be underestimated. However choosing this move gives up other coverage options. Sludge Wave isn't as powerful and lacks STAB. 

Goodra as a mono-Dragon Pokemon sports average bulk but stands out from other Pokemon with its access to Power Whip. While Dragon-type resistances already resist Water-type attacks, the option of Power Whip enables Goodra to close out fights more easily when shields are down, and also enables certain wins that other Dragon-types may struggle against, such as vs Lapras. While it's not enough to overpower the popular Azumarill, it does make the matchup a lot tighter. 

Goodra's access to the powerful Dragon Breath is overshadowed by it's somewhat unimpressive charge moves for Ultra League. Dragonite's access to Dragon Claw and Kingdra's access to Octazooka makes Goodra somewhat of a downgrade by comparison. 

Goodra would prefer to play in Premier Cup rather than open Master League in order to avoid losing to Dialga. Unfortunately even in Premier Cup Goodra takes a back seat compared to existing meta Pokemon due to losing against them, with Dragonite and Garchomp claiming relatively comfortable wins. At the very least Goodra is much more favorable against Rhyperior (Smack Down) compared to Dragonite.