Combos Utilizing Cathodion

sac cathdion to altar. float 5 mana. cathodion returns to hand. cast cathodion (2 mana floating). sac it to altar. float 7 mana. repeat for infinite mana

one cathodion in graveyard, another in play. sac one to put other into play. use 3 mana to cast nightmare. infinite loop. cast hunting pack to put infinite 4/4 beast tokens into play

one cathodion in graveyard, another in play. sac one to put other into play. use 3 mana to cast nightmare. infinite loop. cast graves to return all creatures from graveyard to your hand

sac cathdion to altar. float 5 mana. cathodion returns to hand. cast cathodion (2 mana floating). sac it to altar. float 7 mana. use infinite mana for charge counter on choker be4 it goes to opponent.

sacrifice cathodion for 5 colorless mana using ashnod's altar. then put it on top of your library using haunting crossroads and bog initiate. then let priority take over for fecundity to draw it.

replace cathodian with priest of gix to get the same combo but with black mana instead of colorless

imprint cathodion on soul foundry and make a copy, sac the copy and untap the gat three mana to your manapool and untap foundry with dross scorpion and over again and again and again and...

one cathodion in graveyard, another in play. sac one to put other into play. use 3 mana to cast nightmare. infinite loop. cast wing shards to destroy all opponent's attacking creatures

one cathodion in graveyard, another in play. sac one to put other into play. use 3 mana to cast nightmare. infinite loop. cast steel. attack with creature targeted by steel

Sac cathodion to megatog to get huge, use mana from cathodian to activate shard; rinse and repeat using dross scorpion to untap skeleton shard