For example, almost every Blue-based control deck has access to Castle Vantress, which provides an easy way to trigger Council Deliberations graveyard ability at very little cost
Binding the Old Gods
Nashi, Moon Sages Scion Nashi, Moon Sage's Scion is another mono-black rat ninja like Ink-Eyes, Servant of Oni, but it has a ninjutsu ability that costs 1 mana less and a more valuable combat damage trigger that affects all players rather than just one opponent
Present Arms swaps your library with another deck you own from outside the game and use that one instead ("library" and "deck" both refer to the same thing, but the former is used to refer to it in-game, whereas the latter is used to refer to it outside of the game)
Its design was actually finished in 2014, but the schedule couldnt allow for its release until three years later
Stellas abilities may not be the most original in implementation, but she is cheap to cast, immediately impactful and has an infinitely high power ceiling