Rakdos Purging Simulant

During each combat, you must sacrifice a
creature. If you sacrificed a red creature with
converted mana cost of 4 or greater. Trigger
spells or abilities on or during your end step
an additional time. Spells or abilities that
trigger during or on an opponent's end step
don't trigger. If you sacrificed a black creature
with converted mana cost of 4 or greater. Trigger
spells or abilities on or during your upkeep an
additional time. Spells or abilities that trigger
during or on an oppone