Captain Rex Nebula

At the beginning of combat on your turn, choose target nonland permanent you control. Until end of turn, it becomes a Vehicle artifact with base power and toughness each equal to its mana value, and it gains crew 2 and "Crash Land — Whenever this Vehicle deals damage, roll a six-sided die. If the result is equal to this Vehicle's mana value, sacrifice this Vehicle, then it deals that much damage to any target."

Rune of Protection: White

{W}: The next time a white source of your choice would deal damage to you this turn, prevent that damage.
Cycling {2} ({2}, Discard this card: Draw a card.)

Heartless Hidetsugu

{T}: Heartless Hidetsugu deals damage to each player equal to half that player's life total, rounded down.

Rune of Protection: Red

{W}: The next time a red source of your choice would deal damage to you this turn, prevent that damage.
Cycling {2} ({2}, Discard this card: Draw a card.)

Rune of Protection: Artifacts

{W}: The next time an artifact source of your choice would deal damage to you this turn, prevent that damage.
Cycling {2} ({2}, Discard this card: Draw a card.)