There are a lot of card games you could get into. Magic The Gathering, Pokémon, Yu-Gi-Oh! Duel Links, hell, even the Final Fantasy TCG is pretty fun, but if you're looking for sheer polish and attention to detail, Hearthstone is your game. In addition to the brand new 135-card expansion--The Boomsday Project--that was released at the beginning of this month, Blizzard has added a new Solo Adventure titled "The Puzzle Lab" which tasks players with lethal puzzles, mirror puzzles, and more. The best part? It's totally free.

There are more than 100 puzzles designed to test your knowledge of card interactions and quick maths. Players who clear every laboratory are rewarded with unique card back which you can check out below. Players also receive three free packs of cards from The Boomsday Project just for logging in (I would really appreciate Zilliax for my Odd Paladin deck).

In case you were wondering what I meant by lethal and mirror puzzles, you can check out Blizzard's description of each of the adventure's types of puzzles below:

• Lethal (Destroy the enemy hero): In this experiment, the assistant is tasked with neutralizing the opponent in one turn using the cards at their disposal. We expect this will provide valuable insights into the destructive properties of many of our inventions.
• Mirror (Create a perfectly mirrored battlefield): These tasks challenge the assistant to create a board state where both sides are perfect mirror images of each other: minion positioning, health, attack, etc. This should yield plentiful data on various means of board manipulation.
• Board Clear (Clear the battlefield of minions): Pretty straightforward: clear the board of all minions. Our research suggests that minions play an important role in winning matches, and this set of challenges will help us better understand how to get rid of them.
• Survival (Survive the enemy Hero Power): Finally, the Survival trial requires the test subject to restore their own health in order to survive their opponent’s next onslaught. A recent study has shown that dropping to zero health inversely correlates with winning games, and this experiment will further explore that relationship.

The Puzzle Lab has really been working for me to break up the pace of climbing the ladder and scrapping in the arena. It works some different muscles that, in the end, should make you a better Hearthstone player. It's even easy to restart the puzzle when you misplay as the "End Turn" button has been transformed into a "restart" one complete with a cool animation.

The Puzzle Lab is available to play for free as a part of Hearthstone's latest expansion: The Boomsday Project. You can check out more about those new cards here.