There are Elf cards that make tokens when you play another Elf, like Lys Alana Huntmaster, and this allows Cloakwood Swarmkeeper to build up counters to make your battlefield get out of hand quickly
I dont trust this breakdown very much for several reasons, but Im still going to use it, and Ill talk about why in a bit
So unless you have some self-discard synergy of your own, he would almost become unplayable after a certain point
Tokens, cards that aren't meld cards, or meld cards that don't form a meld pair can't be melded
Being able to remove the notoriously annoying location The Queen's Castle, for example, could easily justify Hide Away on its own
However, the booster box clearly needed a rethink