The Den is where you house all of your wolves and can organize them.

Layout
On the left, you'll find your tabs and wolves. On the right, you can see your den's location, Nana (an NPC that plays with your companion for pebbles), den statistics, and action buttons such as organizing your wolves.

Under each wolf's image, you'll see their name and sex marker icon:
♀ - female
♂ - male
Sexes can be changed with the "Sex Swap" premium item, which changes both the sex and the pose.

Below your wolves, you'll see their level, stamina bar, and icons indicating various statuses (breeding readiness, apparel, alpha status, breeding cooldown, nest readiness, birth readiness, companion status, and sale or stud status).

Slots
Slots determine your total wolf capacity. You start with 10 slots, and you can expand your den for pebbles (under "Actions"). Each expansion grants 1 additional slot. Your total slots are displayed under Den Statistics.

Tabs
By default, you have one tab, but you can purchase more by clicking "+New Den." Switch between tabs by clicking their names.

On the right side, you'll see your pack's location map. Click the pencil icon to set coordinates or rename the den. Modify coordinates anytime or delete them by clicking the "X" next to the displayed coordinates.

Actions
Use the actions box to feed your wolves, organize them, and expand your den. Feed all hungry wolves at once with the "Feed All" button, organize your wolves using the second button, and expand your den with the final button.

In Organize mode, rearrange wolves by dragging and dropping (desktop) or using arrows (mobile). Save positions with the "Save Positions" button. Move wolves between tabs by checking boxes and selecting the desired tab in the pop-up menu.

Nana
Nana is a friendly NPC who loves companions. When a companion is off cooldown, click the green "Yes, Play All" button to play with all companions at once for a set amount of pebbles per companion. Rewards, including XP and items, are listed in the pop-up.