this deck is really effective if your opponent play mono color deck -  Karma + Mind Bend

 

Karma

Enchantment

Abilities: At the beginning of each player's upkeep, Karma deals damage to that player equal to the number of Swamps he or she controls.

8th ed.

common

 

 

Mind Bend

Instant

Abilities: Change the text of target permanent by replacing all instances of one color word with another or one basic land type with another. For example, you may change "nonblack creature" to "nongreen creature" or "forestwalk" to "plainswalk." This effect doesn't end at end of turn.

8th ed.

 

basicly you cast your Karma then Mind Bend to change swamps to whatever land your opponent control the most.. , put a few counter spells to protect your karma and let it do its job. sucking your opponent life point slowly. 

 

this is a really cool combo, try it and let me know if it works downwithsystem540@yahoo.com

sao nguyen