Whenever you attack, you may discard a card. When you do, put a +1/+1 counter on target attacking creature. It gains trample until end of turn.
Whenever you discard one or more cards, exile the top card of your library. You may play that card until your next end step.

All Sliver creatures have flying.
All Slivers have "If this permanent would be put into a graveyard, you may put it on top of its owner's library instead."

This creature enters with four -1/-1 counters on it.
Wither (This deals damage to creatures in the form of -1/-1 counters.)
Whenever you cast a black spell, remove a -1/-1 counter from this creature.
Whenever you cast a green spell, remove a -1/-1 counter from this creature.

At the beginning of your upkeep, you lose 1 life.
At the beginning of your upkeep, you may return target creature card from your graveyard to the battlefield. That creature gains haste until end of turn. Exile it at the beginning of the next end step.

Flying, trample
When Orcus enters, choose one —
• Each other creature gets -X/-X until end of turn. You lose X life.
• Return up to X target creature cards with total mana value X or less from your graveyard to the battlefield. They gain haste until end of turn.

(: Add .)

Return target creature to its owner's hand.

Whenever you cast a noncreature spell, create a 1/1 colorless Hero creature token. If four or more mana was spent to cast that spell, draw two cards. If eight or more mana was spent to cast that spell, sacrifice Tellah and it deals that much damage to each opponent.

This land enters tapped unless you control a Forest or an Island.
: Add or .

Tap X target creatures.
Ferocious — If you control a creature with power 4 or greater, those creatures don't untap during their controllers' next untap steps.

As this enchantment enters, choose Flavorful or Bland.
• Flavorful — Whenever a creature you control with flavor text enters, draw a card.
• Bland — Whenever a creature you control without flavor text enters, draw a card.

When this enchantment enters, exile another target nonland permanent.
When this enchantment leaves the battlefield, return the exiled card to the battlefield under its owner's control.

Return target creature card from your graveyard to your hand.

Flying; banding (Any creatures with banding, and up to one without, can attack in a band. Bands are blocked as a group. If any creatures with banding you control are blocking or being blocked by a creature, you divide that creature's combat damage, not its controller, among any of the creatures it's being blocked by or is blocking.)

When this creature enters, target opponent skips their next combat phase.

: This creature deals 1 damage to target attacking or blocking creature.

Flying, trample
Humans you control get +1/+1.
Coven — Whenever Sigarda attacks, if you control three or more creatures with different powers, look at the top five cards of your library. You may reveal a Human creature card from among them and put it into your hand. Put the rest on the bottom of your library in a random order.

Choose target nonland permanent. Its owner may put it on top of their library. If they do, Clash of Elements deals 2 damage to them. If they didn't put the card on top of their library, they put it on the bottom.

Converge — Exile target nonland permanent if its mana value is less than or equal to the number of colors of mana spent to cast this spell.

Trample
Whenever Borborygmos deals combat damage to a player, put a +1/+1 counter on each creature you control.