It looks like the golduck on kammados kimono has exaggerated features to make it look scary. It kinda looks like a kappa(Japanese folklore river monster) the way it is designed. : r/PokeLeaks
The Pokémon Sprite Guy: 55. Golduck
Pokemon Golduck 35/62 1st Edition Values - MAVIN
Golduck Pokédex: stats, moves, evolution & locations | Pokémon Database