You can check out game guide on 12SKY LAST EMBER
Guild war
When entering a guild war, players of both guilds can attack each other without PK penalties. ■ Guild war conditions - The guild must have at least 15 members. - Only the guild master and sub guild master have the authority to declare hostility. - The maximum number of hostilities is 15. ■ Declaration of war - If the opposing guild does not agree to the declaration of hostility, the hostility will be automatically established if guild members of the opposing guild are killed 10 times. (PKs that occur at this time will be subject to penalties.) - When a hostility is established, players belonging to both guilds will not be in a 'combat state' during battle, and PK penalties will not be applied when the opposing guild dies. - Characters in the opposing guild will lose 3% EXP upon death. ■ Surrender Request - The Guild Master can send a surrender request by touching the “Surrender request” button. - The “Surrender requests” button will be activated 14 days after the start of the war. - After “Surrender requests”, the hostile state can be lifted only after the enemy guild master accepts it. ※ If there is a hostile guild in war, the guild cannot be disbanded.