Odin finally revealed his secret, but as expected, it wasn't something that anyone could pull off. Rather than that, it was already awesome that he could use those three simultaneously and extend that ability to all of his spells.
"After studying Gungnir for many years, I mastered those three types of magic and then extended its effects to all my other attacks, but I only reached that level with that single goal in mind," Odin explained. "I think many can copy me and do the same after practicing for a few years, but only if you forget all the other applications of those skills. I did that and thanks to it, my abilities stagnated for a while and when the time came, I failed in causing any real damage to Ymir."