This card does not target. (You choose a card when this card resolves.)
You can also choose a Fusion, Synchro or Xyz Monster. (In that case, they are returned to the Extra Deck.)
If "G.B. Hunter" is on the field, you cannot activate "Dragoroar". Also, if "Call of the Haunted" is chained to "Dragoroar", Special Summoning "G.B. Hunter", you cannot return cards from the field to the Deck. (This effect is not applied.)
A "Plaguespreader Zombie" that was Special Summoned by its own effect can be chosen by "Dragoroar". In that case, it is banished instead of being returned to the Deck.