Halls of Mist is a rare Land card from Ice Age (ICE), collector number 354. Current market price: $3.86, TCGplayer market prices via Scryfall.
Cumulative upkeep {1} (At the beginning of your upkeep, put an age counter on this permanent, then sacrifice it unless you pay its upkeep cost for each age counter on it.) Creatures that attacked during their controller's last turn can't attack.