The single most important thing to consider when playing JollyGrim is positioning your cards. Every card has a different movement and attack range. If you attack an enemy card from within its attack range, you will be counter attacked. Therefore, it is best to check the opponent's card's attack array before attacking. If you can attack an enemy card from outside of its range make sure to do so at every opportunity.
Pay careful attention to the attack, defense, and speed values before you attack. Try to attack with your card's strongest side, hopefully attacking the enemy card's weak side.
JollyGrim is very flexible when it comes to creating strategies. You can win using many different strategies, so use your own creativity to come up with a plan. It is often a good idea to attack using a few cards in conjunction with each other, but beware of enemy area attacks. Cards such as Ebenezer Scrooge can hit multiple cards at once if he is in a good position.
Attacking with long ranged cards is a great strategy, but they are vulnerable to melee attackers when they can get in close. To counter to a more defensive strategy, try using a "Bloody Mary" card. Bloody Mary's skill "BMx3" can teleport her across the grid to attack weaker ranged cards. She also deals damage over time to any cards in her proximity due to her "Decay" skill.
Experiment with these basics and utilize the unique skills in the game to create effective strategies on your own.
