Unwinding Clock

Untap all artifacts you control during each other player's untap step.

Rebbec, Architect of Ascension

Artifacts you control have protection from each mana value among artifacts you control.
Partner (You can have two commanders if both have partner.)

The Millennium Calendar

Whenever you untap one or more permanents during your untap step, put that many time counters on The Millennium Calendar.
{2}, {T}: Double the number of time counters on The Millennium Calendar.
When there are 1,000 or more time counters on The Millennium Calendar, sacrifice it and each opponent loses 1,000 life.