This deck is built around Dryads, attachments and Kuromo abilities that allow you to repeat or boost "Play:".
Everything in this deck revolves around Mutaform abilities of dryads, it's the main theme.
Most attachments allow you to strike outside the fight phase while boosting your allies in some way. Castle allows you to move attachments between your allies, which makes it easier to get them back in hand or extract extra use of them. Discarded allies still provide lots of utility because enough of cards play around allies in the discard pile.
As a result this deck is pretty powerful and has no trouble of beating any lvl 3 Horde consistently.