Flying, first strike, trample, lifelink, haste

At the beginning of combat on your turn, other Spiders you control gain flying, first strike, trample, lifelink, and haste until end of turn.

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.

First strike, vigilance, trample

At the beginning of combat on your turn, another target Elemental you control gains myriad until end of turn. (Whenever it attacks, for each opponent other than defending player, you may create a token copy that's tapped and attacking that player or a planeswalker they control. Exile the tokens at end of combat.)

+1: Create a 3/3 Kavu creature token with trample that's all colors.

−3: Choose up to two target creatures. For each of them, put a number of +1/+1 counters on it equal to the number of colors it is.

−6: Return target multicolored card from your graveyard to your hand. If that card was all colors, draw a card and create two Treasure tokens.

Jared Carthalion can be your commander.

Flying

: Search your library for a Dragon permanent card and put it into your graveyard. If you do, Scion of the Ur-Dragon becomes a copy of that card until end of turn. Then shuffle.

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

When Niv-Mizzet enters, reveal the top ten cards of your library. For each color pair, choose a card that's exactly those colors from among them. Put the chosen cards into your hand and the rest on the bottom of your library in a random order.

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.

Changeling (This card is every creature type.)

As the game begins, if this creature is your commander, choose two creature types. For the rest of the game, treat those two types like they're the same among your creatures and creature cards everywhere.

, : Choose a creature type. Draw a card for each creature you control of that type.

Flying

Whenever this creature deals combat damage to a player, you may cast a spell from your hand without paying its mana cost.

Flash

Flying, trample, haste

When Nira, Hellkite Duelist enters, the next time you would lose the game this turn, instead draw three cards and your life total becomes 5.

Haste

At the beginning of each player's upkeep, that player untaps Karona and gains control of it.

Whenever Karona attacks, creatures of the creature type of your choice get +3/+3 until end of turn.

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.

: Destroy target creature blocking or blocked by Cromat.

: Cromat gains flying until end of turn.

: Regenerate Cromat.

: Cromat gets +1/+1 until end of turn.

: Put Cromat on top of its owner's library.

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.

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.

Flying, vigilance, lifelink, haste

At the beginning of your second main phase, the player to your left gains control of Elusen, the Giving.

Whenever a player donates a permanent to another player, the donating player draws a card, gains 1 life, and creates three Treasure tokens.

As Rukarumel enters, choose a creature type.

Slivers you control and nontoken creatures you control are the chosen type in addition to their other creature types. The same is true for creature spells you control and creature cards you own that aren't on the battlefield.

, : Create a 1/1 colorless Sliver creature token.