So what's the benefit of linking your account?

DevPlay is Devsisters' global game service platform, which connects and manages Player across multiple games under a single account. If you link your account, you can continue using your existing game data even after switching devices, and the process of logging back in via various login methods becomes more convenient.

Login convenience breaks down into two aspects.

• Automatic token renewal keeps authentication from being interrupted, reducing the hassle of having to log in again every time.
• If there's a DevPlay account that has already been used on the same device, it suggests linking to the existing account based on the device-specific identifier, reducing account confusion.

On the other hand, if you want to play right away, a Guest account is also possible. However, since Guest accounts are tied to the device or app lifecycle, you may lose your account if you change phones, in which case you need to recover it through the customer support page.

Another key benefit of account linking is Cross-Game Promotion (CGP). For example, if you achieve a certain condition in Cookie Run: Tower of Adventures, a reward is generated in the Cookie Run: Kingdom account linked to the same DevPlay account, and the user can log back into Kingdom to receive the reward.

It can also be designed so that rewards can be received later even if accounts aren't linked yet. If the condition is achieved first and the account is linked later, the reward that hasn't yet been paid out is recorded at the Member level and paid out at the time of linking.

However, this kind of structure can also invite abuse attempts such as resetting/rerolling accounts. To prevent this, the DevPlay server maintains fairness through defensive logic such as duplicate payout prevention based on reward id, limited use of Star Coal, the currency dedicated to CGP, and a one-time call limit on the mission achievement API.