Scout's Warning : Instant speed 1 white mana spell that gives your next creature flash, and draws you a card to replace it when cast
Rather than list 20-30 Stellar Sights cards and Special Guests , Ill just tag them all upfront since there are plenty of great cards within those supplementary add-ons
In limited, make sure to fill your side of the board with creatures like Imperial Subduer which will tap down beefy blockers, uncommon Selfless Samurai that will add Lifelink to solo-attackers, or Peerless Samurai, which will reduce the cost of your next spell cast that turn, effectively ramping you
You ramp Yidris out early, ensure he connects with an opponent, and then unleash a torrent of spells, each cascading into another free spell from your library
Use it as a benchmark
Mana produced by the second ability can't be spent to pay the costs of abilities of Shrines you control