The big questions are what payoffs exist and where they fall on the curve
Instant ability allows searching your deck and outside game for four different legendary creature cards, revealing them
As designers add complexity to a card, they more often than not make it less fun to play
While you can use it as ramp in an artifact creature heavy deck, it can turn into a hidden win condition with the right cards
National Champion Ali Aintrazis Top 16 deck from Grand Prix: Charleston: "Ali Aintrazis Five-Color Door" Creatures (6) 1 Angel of Serenity 4 Thragtusk 1 Griselbrand Planeswalkers (4) 1 Garruk, Primal Hunter 1 Nicol Bolas, Planeswalker 1 Tamiyo, the Moon Sage 1 Vraska the Unseen Spells (23) 2 Abrupt Decay 3 Sphinx's Revelation 2 Rakdos's Return 2 Ranger's Path 3 Lingering Souls 3 Supreme Verdict 4 Farseek 1 Oblivion Ring 1 Door to Nothingness 2 Chromatic Lantern Angel of Serenity, Griselbrand, and Garruk, Primal Hunter in the same deck
Basically, barring extreme decks with no generic mana costs at all, if youre playing Commander youre playing Sol Ring
