Transformers Prime

In an upcoming (or currently playing if you live in Canada) story arc that will serve as this season of Transformers Prime's finale, an all too familiar world devouring entity whose name is not Galactus will make his presence felt.... At some level. 
The full extent of Unicron's role in the season 1 finale is still unclear, in the first part of the arc only his face is seen briefly, but with Megatron accepting his role as being something of the Cybertronian anti-christ and herald of Unicron (having mentioned hearing the will of Unicron as far back in the series as episode 3) this could be an interesting way to wrap season 1, who knows maybe Megs will start calling himself Galvatron too!