The admirals that were introduced in commission. Aokiji, Kizaru, Akainu, and Fujitora, literally Blue Pheasant, Yellow Monkey, Red Dog, and Purple Tiger.
As you all know, the admirals all have aliases named after animals. Aokiji, Kizaru, and Akainu are taken from the Japanese Momotaro Legends, with their colors being the three primary colors. Fujitora is not known which mythology it is taken from (or if it even is derived from one), but with its color being a secondary color.
Now, I might be acting a little patriotic, but... In the Korean Dangun Mythology, there is a tiger and a bear, who both ask Dangun to turn them into humans. Since there's already the tiger, there could be a new admiral with a bear theme... any opinions?