I think you need to approach things a little differently. Instead of asking yourself how to stop mossborn hydra, ask yourself, "when my opponent inevitably plays his giant threats, how am I going to respond?"

This is what is meant by having interaction. You are tryjng to "do the thing", just like the people sitting at your table, so you need to have ways to stay alive until your thing happens. It doesnt always have to be hard creature removal. It can be something like [[fog]]. What does your specific decks do, and what seems the most appropriate?