ParleyAn ability word has no rules meaning of its own. It groups abilities with similar themes; the text following it explains this card’s effect. (CR 207.2c) — Whenever this creature attacks, each player reveals the top card of their library. For each nonland card revealed this way, you
investigate“Investigate” means “Create a Clue token.” See rule 111.10f. (CR 701.16). Then each player draws a card.
At the beginning of your end step, you may
untapTo untap a permanent, rotate it back to the upright position from a sideways position. Only tapped permanents can be untapped. (CR 701.26) all lands you control. If you do, you can't
castTo cast a spell is to take it from the zone it’s in (usually the hand), put it on the stack, and pay its costs, so that it will eventually resolve and have its effect. A player may cast a spell if they have priority. See rule 601, “Casting Spells.”
To cast a card is to cast it as a spell. (CR 701.5) spells until your next turn.