Riot's biggest failure when Balancing Mordekaiser.

I've always held the belief that Mordekaiser is healthiest as a low-mobility AP Bruiser. Rumble and Kennen are perfect examples of that.

The biggest issue I've noticed with how Riot has tried to balance him (and I'm referring to Old Mordekaiser here) is that they never recognised that fact that his 'power budget' (the amount of overall power in his kit that Riot divides and allocate to all of a Champion's abilities) ever actually matched that of Rumble and Kennen.

This means that when Riot went to tweak (Old) Mordekaiser, they were making trade-offs. RIOT FINALLY GAVE MORDEKAISER SOME SORT OF MOBILITY IN 5.4 - but they lowered the damage that his W dealt. Even then, Mordekaiser still needed more mobility. A passive on his Q, or Movement speed toward champions that he uses R on.

Then Riot gave up. They decided to rework him.

Months later, his rework comes out and they've finally given him a bigger power budget. But they shifted most of his power into Q as well as gimmicky passives on W and R. His W and E as combat abilities were actually much weaker. But it didn't matter because taking a dragon = free mid tower and you always won lane because you were multiple levels ahead of your opponent. As soon as that was nerfed, Mordekaiser fell off the face of the earth.

Nowadays his power budget is probably about the same as old mordekaiser, but is diluted by his W and R passives.

Take this with a grain of salt. I was only ever a Mordekaiser enthusiast - never a dedicated Mordekaiser main. Some of this might be subjective, or not relevant to how other people played Mordekaiser. I just always felt that Old Mordekaiser wasn't that far off competitive viability, and the Riot gave up on him and did his (failed) rework.