Trample

Whenever Yidris deals combat damage to a player, as you cast spells from your hand this turn, they gain cascade. (When you cast the spell, exile cards from the top of your library until you exile a nonland card that costs less. You may cast it without paying its mana cost. Put the exiled cards on the bottom in a random order.)

Legendary creatures you control get +X/+X, where X is the number of legendary creatures you control.

Whenever you cast a legendary spell from your hand, exile cards from the top of your library until you exile a legendary nonland card with lesser mana value. You may cast that card without paying its mana cost. Put the rest on the bottom of your library in a random order.

Whenever this creature deals combat damage to a player, create a 1/1 colorless Sand creature token for each land you control.

Vigilance, trample, haste

: You may play target Elemental card from your graveyard without paying its mana cost.

Protection from monocolored

Whenever you cast a spell with hybrid mana in its mana cost, copy it. You may choose new targets for the copy.

Whenever this creature deals combat damage to a player, draw that many cards.

, Discard a card: This creature gets +1/+1 until end of turn.

Whenever you cast a signed spell or play a signed land, copy it. (A signed card is a card signed by its artist, designer, or someone else it's strongly associated with.)

Discard a signed card: Destroy target creature with a name that has a five or fewer letter length difference from the person who signed the discarded card.

Vigilance, menace, trample, haste

Whenever one or more Mutants, Ninjas, and/or Turtles you control deal combat damage to a player, put a +1/+1 counter on each of those creatures and draw a card.

Flying, hexproof from multicolored

Whenever Niv-Mizzet deals combat damage to a player, it deals X damage to any target, target player draws X cards, and you gain X life, where X is the number of different color pairs among permanents you control that are exactly two colors.

Vigilance, haste

As Saskia enters, choose a player.

Whenever a creature you control deals combat damage to a player, it deals that much damage to the chosen player.

Flying, trample

Whenever O-Kagachi deals combat damage to a player, if that player attacked you during their last turn, exile target nonland permanent that player controls.

Sliver cards in your hand have warp .

Sliver creatures you control have "When this creature enters, conjure a random card from the Slivers Spellbook into the top ten cards of your library at random, then draw a card."

Warp

When this Siege enters, exile cards from the top of your library until you exile two nonland cards with mana value 4 or less. You may cast one of those two cards without paying its mana cost. Put one of them into your hand. Then put the other cards exiled this way on the bottom of your library in a random order.

If The Snapstone Wielder is your commander and your deck contains no land cards, your starting hand size is four and for the rest of the game, at the beginning of your upkeep, you get a mana counter. During each of your turns, you can spend mana of any color equal to the number of mana counters you have. (You want mana on opponent's turns, you're on your own. Who needs instant-speed interaction—)

Whenever The Snapstone Wielder enters or attacks, cast a random nonland Magic card without paying its mana cost. If it has targets, choose the targets at random.

As long as this creature is your commander, you may play cards from any game in your deck as long as they can be reasonably translated into Magic. They all fit within this Commander's color identity.

: Create one resource of any type. (Mana or otherwise.)

Flying, menace, haste

Whenever this creature attacks, draw two cards.

The "legend rule" doesn't apply to Slivers you control.

Each Sliver creature card in your graveyard has encore , where X is its mana value.

Encore (, Exile this card from your graveyard: For each opponent, create a token copy that attacks that opponent this turn if able. They gain haste. Sacrifice them at the beginning of the next end step. Activate only as a sorcery.)

Flying

At the beginning of combat on your turn, roll the party die and create a number of Treasure tokens equal to the result. (Your party consists of up to one of each of Cleric, Rogue, Warrior, and Wizard. If your party size is 1, the party die is a d4. It's a d8 for 2, a d12 for 3, and a d20 for 4.)