There are many special achievements in "Monster Hunter: The Wild", and Inseparable Achievement is one of them. To achieve Inseparable Achievement, you must first complete 100 missions in the minion attack state. You can only bring the minion cat when hunting alone and double.
What to do with Monster Hunter's Inseparable Wild Achievement
Inseparable
Proof of completing 100 missions in the minion's attack state
You can only take the minion's cat when hunting alone and double. Try not to send rescue signals (even if there is no real person joining, there will be AI replacement cats).