Select the "Hands Of Flame" deck once you have unlocked the "Dragon's Claw" 
card, and play the first opponent in Campaign mode, Chandra Nalaar. Once the 
game begins, you will have seven cards in your hand. Restart the battle until 
"Dragon's Claw" is in your hand. Play it immediately, and wait out Chandra 
Nalaar's attacks. Defeat her monsters with spells and however else you can 
defeat them without reducing her life points to 0. Eventually with her red deck 
and your red deck, you should get the "Life Preserver" achievement in a matter 
of a few rounds. Once you have enough monsters to total 20 or more damage to 
Chandra Nalaar's life points, attack. This implies that all of her monsters she 
summoned earlier have already been defeated. Note: The Mage difficulty is 
recommended.