Sadro, there is a hint on the mission, to merge and split. If still stuck, it took me 3 different ways before getting the part between the merge and split correct
The higher amount transmutes are still only giving 5 instead of like 50 for 1000, as you see only 5 bars pop out and not 50... Just lost heaps of materials!
 "Factory missions"){kind=icon}
 "Woodclicker"){kind=icon}
 "Shape Fold Animals"){kind=icon}
 "Relive Your Life"){kind=icon}
 "Invertion"){kind=icon}
 "Cursed Dungeon"){kind=icon}
 "Villainous"){kind=icon}
 "Demons Took My Daughter"){kind=icon}