Barrensteppe Siege — Tarkir: Dragonstorm Promos #171p

As this enchantment enters, choose Abzan or Mardu.

• Abzan — At the beginning of your end step, put a +1/+1 counter on each creature you control.

• Mardu — At the beginning of your end step, if a creature died under your control this turn, each opponent sacrifices a creature of their choice.