Dft or tld on xerath?

DFT. Late game it's all about spamming Qs.

Deathfire.

While Thunderlord is good at the start of laning phase. once Mid-Late game rolls around you will be staying as far away from champs as possible and throwing Q's all over the place.

Hitting multiple champs and burning them with Deathfire is much better then trying to Thunderlord the front tank.

I run DFT because you can't really proc TLD without throwing in an auto attack and putting yourself your executing your at risk for taking damage back or throwing out your combo and hoping you hit everything and DFT further enhances your poke

Just depends on how you want to play laning phase