Ja-Niviri, God of Murder

When Ja-Niviri, God of Murder entets the battlefield destroy a creature you control and a creature an opponent controls if there total power does not add up to 6 Ja-Niviri, God of Murder cannot block
{r}{r} Gains your choice of haste, Vigilance, First strike, or Infect until end of turn
When Ja-Niviri, God of Murder leaves the battlefield you may return it to its owners hand