Seelenstein-Sanktuarium

If this becomes a creature but you haven't controlled it continuously since your most recent turn began, you won't be able to activate its mana ability or attack with it that turn.

Soulstone Sanctuary's last ability doesn't have a duration. Once it resolves, it will remain in effect until the game ends, Soulstone Sanctuary leaves the battlefield, or some subsequent effect changes its characteristics, whichever comes first.