here's another very good card: "Information"

(to mtg terms)
once per any player's turn:

> Identify a Hand:
= target a player's hand:
":" = and bypass the stack - resolve immediately

>Reveal an Entity from it.
= Look at their hand, and make a Creature in that hand public game knowledge (if they have one)
"." Resolve FILO (normal stack)

>You may Transmute it.
= permanently convert it into a land
(you can do this because there are no dedicated land cards, every card is potentially a land)
"." resolve this FILO (normal stack)

this is a very good card because it only costs 1 (it can be played on turn 1), it's a wall, it gives you hand knowledge even if they don't have a creature, and you can force them to play creatures as energies, narrowing their options.

cards can always be transmuted back to their original type, and also revealed cards can be the target of other effects.