Where Do You Farm Tower 3 Defense Void Keys?

[(PSN)realcurtman94]

im trying to get some more T3 defense void keys. i've tried farming them at kiliken on Venus and triton on Neptune. but no luck what other missions can i try? 

[(PSN)Daikon177]

Try outer terminus or narcissus. I usually see t3 keys as rewards there

[(PSN)Fbeast2]

I have seen T3 keys on almost all survival missions longer than 30 minutes. I just got one on Mimas farming for Oxium.

[.Talia.]

Palus - Pluto 

15 Minutes = T3 Key