First draft of a Goblins deck using Otherworldly Outburst. The main idea is to use lots of goblins which self-sacrifice, are sac outlets, or have abilities which trigger on sacrifice to synergize with both Otherworldy Outburst, Death Spark and in post SB games, Sylvok Lifestaff.

Outside of cards which are directly synergistic, we have Sparksmith which lets us take care of blockers outside of bolt/spark range and Bushwhacker, which is just a finisher.

Sideboard is untested, but covers most of the bases. If you're trying to fit more into the sideboard, I think electrickery could be trimmed down to a 1 or 2 of, as we already have lots of answers for x/1 creatures in the main.