Rather than AoE damage.
Make Deathfire inflict its full damage on AoE attacks rather than half. Give it actual base damage that grows with level and adjust its ratios accordingly.
Suddenly there's a compelling reason why you might want one of them over the other! Because with Thunderlord's scaling down to 15 seconds later in the game, it flat out beats the DPS offered by Deathfire if you proc it twice.
Zantumall1 votesI'm pretty sure Thunderlord's actually is single target. The mastery page tooltip says it's AoE but I think testing has shown that it only affects the champion you proc it on.
Also, giving Deathfire base damage and full AoE duration would probably make it way too strong. It's already really good on anyone who can apply it consistently - 
etc.
Rebonack1 votesI'm pretty sure Thunderlord's actually is single target. The mastery page tooltip says it's AoE but I think testing has shown that it only affects the champion you proc it on.
If true, the tooltip should probably be fixed then.
And Deathfire should still be doing full damage on AoE attacks.