Argh, sorry Godric but no thank you; I already have a Yellow Merge.
My goal here is to give my Gizonde - actually my every spell - its maximum potential. That's why I equip a cloak for a phase of a boss, before to switch to another at the start of the next phase, for instance. Gizonde Merge will be perfect to speedrun PoD and to make the fight against Shambetin as short as possible, among other things.