Commander

Casting Cost: 

+1: Untap two target lands.

-1: Put a 3/3 green Beast creature token onto the battlefield.

-4: Creatures you control get +3/+3 and gain trample until end of turn.

Casting Cost:

Ghave, Guru of Spores enters the battlefield with five +1/+1 counters on it.

, Remove a +1/+1 counter from a creature you control: Put a 1/1 green Saproling creature token onto the battlefield.

, Sacrifice a creature: Put a +1/+1 counter on target creature.

Casting Cost:

Creatures can't attack you unless their controller pays  for each creature attacking you. (This cost is paid as attackers are declared.)

Casting Cost: 

Whenever a creature you control dies, each other player sacrifices a creature.

: Add  to your mana pool.

: Each player gains control of all creatures he or she owns.

Casting Cost: 

Flying

Deathtouch (Any amount of damage this deals to a creature is enough to destroy it.)

When Hornet Queen enters the battlefield, put four 1/1 green Insect creature tokens with flying and deathtouch onto the battlefield.

Casting Cost:

At the beginning of each player's draw step, if Howling Mine is untapped, that player draws an additional card.

Casting Cost:

Whenever Hydra Omnivore deals combat damage to an opponent, it deals that much damage to each other opponent.

Casting Cost:

Untap all creatures and gain control of them until end of turn. They gain haste until end of turn.

Casting Cost:

Flying

Whenever Intet, the Dreamer deals combat damage to a player, you may pay . If you do, exile the top card of your library face down. You may look at that card for as long as it remains exiled. You may play that card without paying its mana cost for as long as Intet remains on the battlefield.

Casting Cost:

Flying

Whenever Kaalia of the Vast attacks an opponent, you may put an Angel, Demon, or Dragon creature card from your hand onto the battlefield tapped and attacking that opponent.

Casting Cost: 

Karador, Ghost Chieftain costs  less to cast for each creature card in your graveyard.

During each of your turns, you may cast one creature card from your graveyard.

Casting Cost:

Equipped creature has haste and shroud. (It can't be the target of spells or abilities).

Equip 

Casting Cost: 

Each player exiles all creature cards from his or her graveyard, then sacrifices all creatures he or she controls, then puts all cards he or she exiled this way onto the battlefield.

Casting Cost:

Whenever Martyr's Bond or another nonland permanent you control is put into a graveyard from the battlefield, each opponent sacrifices a permanent that shares a card type with it.

Casting Cost: 

Join forces — Starting with you, each player may pay any amount of mana. Each player draws X cards, where X is the total amount of mana paid this way.

Casting Cost:

, : Put a fate counter on target permanent.

, , Sacrifice Oblivion Stone: Destroy each nonland permanent without a fate counter on it, then remove all fate counters from all permanents.