RCE is very powerful with a wide range of applications. The "Silence" ability can be used defensively to fizzle spells like Yawgmoth's Will, Dark Petition, Snapcaster, JVP, or just make life miserable for a Storm opponent. It's not bad against PO as well as you can strand Moxen in the opponent's hand after a PO is cast, though not really ideal. It can be used offensively to clear the way for your own combos, like Bomberman or whatever the heck Brian Kelly has up his sleeve (both he and I are both very high on this card). The Tutor ability has several targets across different archetypes including Combo pieces (Ballista, Welder), Hatepieces (Gorilla Shaman), or Value (DRS).
The combination of a relevant creature type, strong base stats, replacement, and an situationally strong ability, makes for a potent package. I plan to try it in several shells and I'm sure it will see play in other formats like Modern and Legacy.