I run a very similar deck, with -2 arsenic +1 vamp dagger +1 acceleration +1 pillar +1 blessing
Any suggestions on upgrade order, to use as an arena farmer?
Not really sure why you put in acceleration. As for an arena farmer, you should go up 6 novas first. They're pretty useful and flexible.
Took out 1 momentum and replaced with a mummy, to make use of all elements.
I put acceleration in because it really helps you outdamage a big rush, and is viable last resort CC for things like devourers or nasty ability creatures. I don't really need the momentums as deflag usually takes care of pesky shields.
If i'd upgrade novas i'd definatley have to remove a few graboids and use mark of entropy... Would be awesome quanta though.