Jeff, Father of All

When Jeff, Father of All enters the battlefield it
deals 20 damage to each dinosaur creature. They
can't be regenerated.
At the begging of each upkeep create a 1/1 green mammal creature token.
"He will wipe away every tear from their eyes, and
death shall be no more, neither shall there be mourning,
nor crying, nor pain anymore, for the former things
have passed away." - Revelation 21:4