In the Ravenswood finale, the Pact Maker (aka "the bad guy") wanted to bring Miranda back so that all five teens could die together, fulfilling the promise that their ancestors made years prior. Miranda's uncle stopped the Pact Maker from completely the task, but did say that Miranda could come back to life.

Does Ravenswood have an ending?

Miranda's uncle succeeded in driving the evil entity out by smashing a clear tube labeled “Caleb.” “Ravenswood” concluded with Max killing Dillon, and ghost Miranda getting her happily-ever-after with ghost Caleb of the past.

What happened to Caleb in Ravenswood?

Caleb faced death in the Season 1 finale and he prevailed, sending the Pact Master back to hell where he came from. Caleb was literally marked for death so now, "A" should just seem like a tip of the iceberg of life. He has nothing really to be afraid of, which makes him integral to the final "A" showdown.