This Secret Mission behaves a little differently to the ones we've seen before
If you have more than two instants or sorceries in your graveyard when this resolves, you get added to your mana pool, making this essentially a Demonic Tutor
If you can protect the Enchanter long enough to get at least one attack in, you can do busted things, like assemble the combo of Phyrexian UnlifePhyrexian Unlife and SolemnitySolemnity over three turns (casting Zur and attacking twice): Even without putting together a combo, Zur can fetch up Stax-style enchanties like Mystic RemoraMystic Remora, PropagandaPropaganda, Ghostly PrisonGhostly Prison, Blind ObedienceBlind Obedience, and many more
As a frame of reference, this card hovered around $1000-$3000 in 2019, but now has an average price of about $15,000
Here's more on those: Your First Victory With all that being said, the goal of the Pokemon TCG is to beat the other player
That said, Lessons decks are pretty hard-up with the limited card pool, so I do actually expect this to keep seeing play
