Board Thread:Questions and Answers/@comment-98.247.13.10-20131102092541/@comment-17670418-20131109163756

You may fuse any daemon with any another daemon. However, fusing the same daemons of the same class (EX: Phantom to Phantom) will give the Daemon more EXP.

Fusing a daemon to a replica (Wind Weaseal ---> Wind Weaseal) will also give a higher EXP boost.

Fusing Magatamas give Daemons a must larger EXP boost.

Some daemons have their own magatamas, which can be fuse to the daemon to raise their skill level to a possible max of level 20. EX: Ramiel has her own Magatama that can be fused to her to raise "Divine Thunder" to level 20, if you manage to get all 7 magatamas. I say seven because she is a four star daemon, and skill levels only go up to 13 for four stars if no magatamas are used. Five star daemons can reach level 70 with a skills level of 15, thus, only need five magatamas to maxed out their skill.

Some daemons have the same skill as other daemons, and they may be fused with each other. EX: All forms of Kotetsu except Focused form may be fused with Kiri, since they both share the same skill, Fiery Spirit.

If you didn't understand a word I said, here's the WIKI page : http://ayakashi-ghost-guild.wikia.com/wiki/Fusion_Tips