lightning warp + rapid decay

Hm. Had forgotten Cold to Fire, probably because I'm stupid. Pyre explodes bodies which is mad cathartic but also, apparently, interferes with prolif in some manner and requires shenanigans, but I do love me some Pyre action.

I'unno. I definitely see what Viper's saying, but dismissing Rapid Decay out of hand on a skill set-up which directly benefits from all of its effects seems...odd, to me. Using it for strictly mobility is not great, yeah, but if you have a skill that needs more DoTz and also less duration...well, why not?

if you can find a way around the Ignite issue, you could substitute Rapid Decay for Chance to Ignite. Rough tree prototype gives me 31% total standing Ignite chance easily feasible for an Elementalist build in the tree alone; get Cloak of Flame and you're up to 41% chance to ignite, and you can get a couple more percentage points with jewels or stuff like Gang's Momentum or Doryani's Invitation if you have to. With Prolif, that should be plenty enough ignite chance to dispense with the Chance to Ignite gem and slot Rapid Decay in there instead for a slightly more nimble Warp and also better degeneration. So like so:

Warp > Cold to Fire > Less Duration > Faster Casting > Controlled Destruction > Rapid Decay

Would that be workable, or am I missing some reason why Prolif doesn't negate the need for 100% ignite chance on a non-Emberwake build?

I once tried a 4l setup for LW and from my experience I can say that you notice quite a bit of a difference when you warp across the entire screen, or when standing on tar or chilled ground. If you can afford to spend another socket on it, the by all means, do it. It gets quite mana intensive though.