Merge H! Myrrh

Hello guys!
I have a H! Myrrh -DEF +RES, and summon another -SPD. How to proceed with the merge? Which one should I merge?

Tks!

What is the boon/asset of the -Spd? After merge only the asset remains. So you would be choosing between +Res and +Asset. You merge the one you don’t want into the one you want. You can always check the outcome of your merge on the merge window before the process is finalized (click Confirm).

The boon is +HP. So I ended up choosing the one +RES.

Tks!!!