Best win condition

What is the strongest, most effiecent and succesfull win condition for the hard control deck at this moment of time in the game? (Any combination of colors)

There really isn’t one. This is not like Magic: The Gathering. There is no equivalent to a card like Maze’s End in this game. The hard Control blanket win condition just doesn’t really exist, but certain Control decks have certain win conditions, for example, G/Y Sacrifice has Soul Eater, and you can build Three Wishes with a variety of win conditions. So there is no blanket win condition, but a fun control deck, if you’re interested, would be Three Wishes. There’s a lot of ways to build it, and it’s really fun to play.