Midnight Guard

Whenever another creature enters, untap Midnight Guard.

Arcane Signet

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

Sol Ring

Sunstrike Legionnaire

Sunstrike Legionnaire doesn't untap during your untap step.
Whenever another creature enters, untap Sunstrike Legionnaire.
{T}: Tap target creature with mana value 3 or less.

Ghired, Mirror of the Wilds

Haste
Nontoken creatures you control have "{T}: Create a token that's a copy of target token you control that entered this turn."