/Canon for Hydra: "Cells" are called "Den's" due to the snake theme within Hydra. Key Agents are given titles of Snakes depending on personality, skill-set etc. Broods are in house codenames for bases or bigger cells. "Den's"are code for safe houses and Rhumba which normally means of pair of snakes is code for a duo pair of agents or duo pair of strike teams depending on their assignment
And thatās how it works.










