I see many oathbreaker decks with these 2 cards, and I don't understand how Thoughtcast somehow gets cast for free once you have enough artifacts in play, with Saheeli, Sublime Artificer on the battlefield? People say that it circumvents the tax, but since only 1 tokens etb after each cast, doesn't that lower the cost by only one mana instead of 2?
I don't know the specific deck you are talking about, but Affinity can only reduce generic costs, so the U has to be paid no matter how many artifacts the player controls. Also, the cost is paid as the spell is cast, so the token created by Saheeli comes way too late to add anything to the spell casting process.
You are correct that the additional token only helps reduce the subsequent cost by 1. They would either have to cast some other spell to get another token or some other way to get an artifact. Just casting the Thoughtcast is not enough to always make its cost {U}
Otherwise, I guess then that Thoughtcast gets to cost one 1 blue if you keep puting the drawn cards, namely artifacts for 0 cost into play, then keep the engine going until you combo off.
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As for the token, I meant that it helps pay for subsequent recasting of Thoughtcast.
Otherwise, I guess then that Thoughtcast gets to cost one 1 blue if you keep puting the drawn cards, namely artifacts for 0 cost into play, then keep the engine going until you combo off.