Gambit Prime Medals for RECKONER are absurdly hard to get as a solo player. It's pushing me over the edge...with my Reaper set on I got a Locksmith medal. Switched to Sentry set and got a Massacre. Aaaaaggghhhh! Basically after playing Gambit Prime as a Reaper a hell of a lot I have TWO Massacre medals out of 10 needed. One Locksmith and one Half-banked for Collector (need 15!). The conditions for these need tuning down so solo players stand any chance, especially Massacre. Oh yeah, and Luke Smith saying that Gambit Prime has improved due to less Invaders is a very funny joke
I like using bottom tree sentinel with doom fangs for massacres. Got 3 in one match that way.
Arcstrider was a must-have for my massacres. I got 8 of them with Way of the Warrior, and another 2 with Recluse and Delirium. I almost Locksmiths more frustrating, but found that Liar’s Handshake and one-two punch made it work.