Choose a companion by the problem it solves: Concentration, Bleed, Burning, mixed pressure or inventory space.
Open the companion system through Myrll
The reported route is: meet Myrll, finish her request, invite her to the Sanctum, repair the broken bridge, reach Beast-Occupied Ruins, defeat the Alpha Wolf and return to Myrll to check the companion trade.
Fangra Cub is the first reported unlock
The tested Fangra Cub used Savage Leap with Strike Damage, Bleeding and Chill. Its reported price was 50 G, but price and ability values are single-run observations rather than fixed EA database values.
Match the pet to the loop
The launch report describes Moon Cat as a Concentration support, Carrion Parrot as a Bleed amplifier, Ember Hound as Fire/Burning pressure and Fangra Cub as a mixed damage-status companion. Choose the pet that strengthens the loop you already use instead of chasing a universal tier list.
Level the companion you actually use
Pet XP changes the value of swapping. The report observed a Level 4 Fangra Cub showing Max Level, but that cap is not a universal promise. Treat pet levels as observed client data until repeated runs confirm the rule.
Use Courier as overflow, not extra storage
Courier can send pet-carried items to a selected Sanctum chest and show available capacity. A full destination chest cannot receive the transfer, so clear space before relying on it to extend an expedition.
Pet Pen behavior is still open
The reported Pen stored inactive companions, but the test did not establish reliable passive XP. Equip the pet you want to level instead of assuming storage alone trains it.
EA scope versus current names
Official launch material confirms nine unique pets with different abilities; the names and roles above come from community testing and should remain visibly marked until the client roster is captured.