Arc Damage for me on this one. Have killed endless thralls, with both arc and solar, but they do not drop anything. This game is starting to piss me off! And I agree with other posts. The reward is stupid. Way too much work for gauntlets. I would rather just spend vanguard marks and buy the new armor. Who at Bungie thinks up this garbage. Does Bungie not take requests from the people that provide their salary (consumers). Heads up Bungie. I WILL NOT BE BUYING ANT MORE FUTURE DLC!