should i kill the final boss lord of cinder or do DLC first

[GhostByte]

iam worried it will end the game or something and not let me do the DLC. also do different endings effect the DLC differently if you play after killing lord of cinder

[Watermelons]

DLCs don't affect any of the endings.
The game will let you decide whether you want to start NG+ after you beat the boss; if you decide not to, you can always do it from the Firelink Shrine bonfire.

I'd say go do the DLCs then end it all with an epic showdown with the SoC

[Baby don't hurt me]

it will let you choose go to NG+ or not
pick no

and yes finish TRC first then defeat soul of cinder will change the ending music

[Taco Cat]

No consequence in doing either first. You can choose to put off going to ng+ or not

[Watermelons]

Originally posted by BabyDontHurtMe:

it will let you choose go to NG+ or not
pick no

and yes finish TRC first then defeat soul of cinder will change the ending music

No it won't, unless I've missed something. Or do you mean the credit music? I thought it was always changed permanently since RC's release