Talk:Fieldron/@comment-68.227.249.27-20150421234748

Easiest way to get these is to wait until there is an invasion. Infenstation missions give you 3 Fieldron as a reward for completing them 3 times. So when several nodes are being invaded you grind them out. Today alone I got 12.

4 nodes x 3 runs each

Each run gave at least 3000 credits  9k x 4 = 36k credits

While you're grinding other goodies will drop ( Fusion Cores, mods) plus you level weapons and warframes while doing it.