FlyingWhen Patagia Viper enters, create two 1/1 green and blue Snake creature tokens.When Patagia Viper enters, sacrifice it unless was spent to cast it.
Other creatures have "Whenever this creature attacks, you may have it fight Grothama, All-Devouring."When Grothama leaves the battlefield, each player draws cards equal to the amount of damage dealt to Grothama this turn by sources they controlled.
When Junkyard Genius enters, create a tapped Powerstone token. (It's an artifact with ": Add . This mana can't be spent to cast a nonartifact spell."), Sacrifice another creature or artifact: Until end of turn, other creatures you control get +1/+0 and gain menace and haste.
Choose one —• Destroy target nontoken artifact or enchantment an opponent controls. Incubate 2. (Create an Incubator token with two +1/+1 counters on it and ": Transform this artifact." It transforms into a 0/0 Phyrexian artifact creature.)• Incubate 2, then transform an Incubator token you control.
Cycling (, Discard this card: Draw a card.)When you cycle Gempalm Incinerator, you may have it deal X damage to target creature, where X is the number of Goblins on the battlefield.
When Fiend Hunter enters, you may exile another target creature.When Fiend Hunter leaves the battlefield, return the exiled card to the battlefield under its owner's control.
Enchant creatureEnchanted creature gets +2/+2 and has ": Regenerate this creature." (The next time the creature would be destroyed this turn, instead tap it, remove it from combat, and heal all damage on it.)
When Rosethorn Halberd enters, attach it to target non-Human creature you control.Equipped creature gets +2/+1.Equip (: Attach to target creature you control. Equip only as a sorcery.)
Threshold — As long as seven or more cards are in your graveyard, Treacherous Werewolf gets +2/+2 and has "When Treacherous Werewolf dies, you lose 4 life."
FlyingWhenever Purifying Dragon attacks, it deals 1 damage to target creature defending player controls. If that creature is a Zombie, Purifying Dragon deals 2 damage to it instead.
When Barbed Spike enters, create a 1/1 colorless Thopter artifact creature token with flying, then attach Barbed Spike to it.Equipped creature gets +1/+0.Equip
Imprint — When Phyrexian Ingester enters, you may exile target nontoken creature.Phyrexian Ingester gets +X/+Y, where X is the exiled creature card's power and Y is its toughness.
As long as you control a Plains, Sejiri Merfolk has first strike and lifelink. (Damage dealt by a creature with lifelink also causes its controller to gain that much life.)