Flying
When this creature enters, target player discards two cards.

Echo (At the beginning of your upkeep, if this came under your control since the beginning of your last upkeep, sacrifice it unless you pay its echo cost.)
When this creature enters, it deals 4 damage to each other creature.

If a source would deal damage to you, prevent 1 of that damage.

Flying
When this creature enters, destroy target nonblack creature. It can't be regenerated.

Each player sacrifices four lands of their choice. Wildfire deals 4 damage to each creature.

Swampwalk (This creature can't be blocked as long as defending player controls a Swamp.)
: Add . Target opponent gains control of this creature. (Activate only as an instant.)

Corrupt deals damage to any target equal to the number of Swamps you control. You gain life equal to the damage dealt this way.

Flying (This creature can't be blocked except by creatures with flying or reach.)
: This creature deals 1 damage to any target.

Serra Avatar's power and toughness are each equal to your life total.
When Serra Avatar is put into a graveyard from anywhere, shuffle it into its owner's library.

When this creature enters, untap up to seven lands.

This creature doesn't untap during your untap step.
Pay 8 life: Untap this creature.
This creature can't be blocked except by three or more creatures.