What set is Summon: Leviathan from
For each of those cards, its owner may play it for as long as it remains exiled
Thats because, also like Clue, you are able to ask other players if they have certain suspects, weapons, or rooms in their pile, but here making those guesses is restricted by Magic mechanics: you get the opportunity to do so only when you either deal combat damage to another player, or exile six mana value worth of cards from your graveyard at the end of your turn
Magic has a lot of big creatures: Krakens, Colossi, Dragons, Dinosaurs, Wurms, Eldrazi, and the list goes on
---- I think this is about the best I'll be able to do
Thoden, King of Rohan may not see much play in high-level tournaments, but could still be a fun and flavorful addition to a casual deck