In the TCG and the OCG , the shortened term " monster " is distinguished from "Monster Card" by referring to Monster Cards that are not being treated as Spell or Trap Cards, for reasons such as becoming Equip Cards or being Pendulum Monsters activated in the Pendulum Zone
As a subtype, Plan can be referenced by other spells and abilities, which is perhaps something Doom specified in his contract
Upstart Goblin Upstart Goblin allows you to draw a card at the cost of giving your opponent 1,000 LP
Ruby, Daring Tracker A mana dork with haste is good value, and having Ruby, Daring Tracker in the command zone could be a nice way to ensure you have some extra mana early in the game
Since its a Basic Pokemon, you can slap it onto the field early, but thats not what makes Roaring Moon ex truly terrifying