Arcane Signet

{T}: Add one mana of any color in your commander's color identity.

Doubling Season

If an effect would create one or more tokens under your control, it creates twice that many of those tokens instead.
If an effect would put one or more counters on a permanent you control, it puts twice that many of those counters on that permanent instead.

Second Harvest

For each token you control, create a token that's a copy of that permanent.

Hare Apparent

When this creature enters, create a number of 1/1 white Rabbit creature tokens equal to the number of other creatures you control named Hare Apparent.
A deck can have any number of cards named Hare Apparent.

Parallel Lives

If an effect would create one or more tokens under your control, it creates twice that many of those tokens instead.

Purphoros, God of the Forge

Indestructible
As long as your devotion to red is less than five, Purphoros isn't a creature.
Whenever another creature you control enters, Purphoros deals 2 damage to each opponent.
{2}{R}: Creatures you control get +1/+0 until end of turn.

Finneas, Ace Archer

Vigilance, reach
Whenever Finneas, Ace Archer attacks, put a +1/+1 counter on each other creature you control that's a token or a Rabbit. Then if creatures you control have total power 10 or greater, draw a card.

Sol Ring

Impact Tremors

Whenever a creature you control enters, this enchantment deals 1 damage to each opponent.

Baylen, the Haymaker

Tap two untapped tokens you control: Add one mana of any color.
Tap three untapped tokens you control: Draw a card.
Tap four untapped tokens you control: Put three +1/+1 counters on Baylen, the Haymaker. It gains trample until end of turn.

Jacked Rabbit

Ravenous (This creature enters with X +1/+1 counters on it. If X is 5 or more, draw a card when it enters.)
Whenever Jacked Rabbit attacks, create a number of 1/1 white Rabbit creature tokens equal to Jacked Rabbit's power.