Combo cards are scattered all over blues history, as well as disruption to make sure your opponents cant combo
Zetalpa, Primal Dawn is also a decent budget commander option if you want to make a Voltron deck focused around it, since this card can deal out good amounts of commander damage
When building around it, look for Food payoffs, artifact-token doublers, sacrifice outlets, and defensive tools that help keep your Food supply intact
Are you playing any new bird cards currently
There are a ton of applications for Underworld Breach , ranging from something as simple as bringing your guys back to using a spell over and over again
Like another card, Soul Spike, that spiked not so very long ago, Sickening Shoal is seeing play in Necrodominance decks