I dont think sunfire is a really useful item, specially for morde, he alredy has creeping death and zhonya is better choice if you want armor, sunfire is only viable for tanks who stack hp, armor and mr (ammumu, rammus, shen)

change your masteries to 9 0 21 and dont get burning embers it's not a good choice compared to 15% magic pen or 15% summoner spell, cd you alredy have too many ap runes, try changing some of them for cdr or magic pen

+1... But take Presence of the Master over Burning Embers, man.
Come on now.

Maybe, i actually didnt try it with this talent. Anyway it works as i wrote, at least worked for me for about 30 games, 20 in a row won ;) maybe with cd reduction on flash it would be even more awesome ;) though the 10 ap is pretty useful early game, it goes a bit margin late game

Don't mean to hate, but there is absolutely no way 10 AP is more valuable than 15% reduced summoner spell CD's =P

Otherwise looks solid.

great , ty alot