Thread:KodachiZero/@comment-27224936-20160214213501/@comment-3215051-20160215023729

The Chain system is unlocked when you reach the Lake of Sand, it allows you to attach a Lv. 40+ character to another character to basically give them another ability. However, this adds cost to use that character. You can add/remove/switch chains as much as you want, provided you have the cost and minimum level requirement. Also, you get stat bonuses for the chain system if you use the same class (Warrior, Knight, Cleric...), same affiliation (Volunteer Army, Soul Island, Lake of Sand...), and the same job (Priest, Grappler, Paladin...) [Zero]