Architect of Thought is still a good card in its own right and is a fine inclusion in your deck when you don't have the Mind Sculptor, sometimes you even play both
A player does not have to reveal the chosen card, so long as it is clear *which* card was chosen
The average damage they do you over the course of a game is lower than that for shock lands, if only by a tiny amount
Its going to be difficult to lose in combat the turn after Lumra comes down, but I dont personally see it holding this price for long
Cormela, Glamour Thief Corpse Appraiser Cutthroat Contender Evelyn, the Covetous Glamorous Outlaw Lord Xander, the Collector Maestros Diabolist Midnight Assassin Sanguine Spy Syndicate Infiltrator Vampire Scrivener
Secondly, the Black Lotus is one of the most powerful cards in the original MTG game, so powerful in fact that by playing it with the right combination of cards, a player could win the game on their first turn