This spell can't be countered. (This includes by the ward ability.)
Destroy target creature or planeswalker with mana value 3 or less.

Search your library for a creature card, reveal that card, put it into your hand, then shuffle.

Each opponent can't cast noncreature spells with mana value greater than the number of lands that player controls.
Whenever an opponent casts a spell, if no mana was spent to cast it, counter that spell.

Equipped creature gets +1/+1 for each color among permanents you control.
As long as this Equipment is attached to a creature, your opponents can't cast spells during your turn.
Equip

Spree (Choose one or more additional costs.)
+ — Copy target instant spell, sorcery spell, activated ability, or triggered ability. You may choose new targets for the copy.
+ — Change the target of target spell or ability with a single target.

Choose target spell or permanent that's red or green. Its owner puts it on their choice of the top or bottom of their library.

: Return this card from your graveyard to the battlefield tapped.

Shadow (This creature can block or be blocked by only creatures with shadow.)
If a card would be put into an opponent's graveyard from anywhere, instead exile it with a void counter on it.
, Sacrifice this creature: Choose an exiled card an opponent owns with a void counter on it. You may play it this turn without paying its mana cost.

Grapeshot deals 1 damage to any target.
Storm (When you cast this spell, copy it for each spell cast before it this turn. You may choose new targets for the copies.)

Sliver creatures you control have flying and haste.

Whenever an Aura you control enters, if you cast it, you may search your library for an Aura card with mana value less than or equal to that Aura and with a different name than each Aura you control, put that card onto the battlefield attached to Light-Paws, then shuffle.

Return up to X target artifact and/or non-Aura enchantment cards each with mana value X or less from your graveyard to the battlefield. If X is 6 or more, those permanents are 4/4 creatures in addition to their other types.

Proliferate, then choose any number of permanents you control that had a counter put on them this way. Those permanents phase out. (To proliferate, choose any number of permanents and/or players, then give each another counter of each kind already there. Treat phased-out permanents and anything attached to them as though they don't exist until their controller's next turn.)

At the beginning of each player's draw step, that player draws an additional card.

This creature gets +1/+0 for each other Rat you control.
A deck can have any number of cards named Rat Colony.

Enchant creature card in a graveyard
When this Aura enters, if it's on the battlefield, it loses "enchant creature card in a graveyard" and gains "enchant creature put onto the battlefield with this Aura." Return enchanted creature card to the battlefield under your control and attach this Aura to it. When this Aura leaves the battlefield, that creature's controller sacrifices it.
Enchanted creature gets -1/-0.

You may have this creature enter as a copy of any creature on the battlefield, except it's an Illusion in addition to its other types and it has "When this creature becomes the target of a spell or ability, sacrifice it."

Flash
Whenever an opponent searches their library, you gain 1 life and draw a card.

Lands you control are every basic land type in addition to their other types.

All Slivers have "Pay 2 life: Return this permanent to its owner's hand."

Whenever a commander you control deals combat damage to an opponent, it deals that much damage to each other opponent.
Partner (You can have two commanders if both have partner.)

When you cast this spell, you gain half X life and draw half X cards. Round down each time.
Flying, trample
This creature enters with X +1/+1 counters on it.

, : Add .

: Exile target card from a graveyard. If it was a creature card, put a +1/+1 counter on this creature and you gain 1 life.

Lightning Strike deals 3 damage to any target.

Search your library for an Aura or Equipment card, reveal it, put it into your hand, then shuffle.

When this creature enters, you may search your library for an Equipment card, reveal it, put it into your hand, then shuffle.
, : You may put an Equipment card from your hand onto the battlefield.

Counter target spell. If that spell is countered this way, put it on top of its owner's library instead of into that player's graveyard.

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 or dies, create a 1/1 red Goblin creature token.

When this creature dies, put target creature card from your graveyard on top of your library.
Dredge 4 (If you would draw a card, you may mill four cards instead. If you do, return this card from your graveyard to your hand.)

Choose one. If you descended this turn, you may choose both instead. (You descended if a permanent card was put into your graveyard from anywhere.)
• Destroy target creature or planeswalker.
• Destroy target noncreature, nonland permanent with mana value 1 or less.

: Add .
: Add or . This artifact deals 1 damage to you.

Take an extra turn after this one. At the beginning of that turn's end step, you lose the game.

Destroy target artifact. It can't be regenerated. Create X 1/1 green Saproling creature tokens, where X is that artifact's mana value.

Whenever equipped creature deals combat damage to a player, you may draw two cards. If you do, discard a card.
Equip (: Attach to target creature you control. Equip only as a sorcery.)

Creatures you control have ": Add one mana of any color."