Breeding Fields

At the beginning of your upkeep, you may tap X untapped Grub-Dog creatures you control. If you do, create X 1/1 green and white Grub-Dog creature token with lifelink named Bulborb
Larva.
Sacrifice X Grub-Dog creatures with toughness 1 or less: You may put a Grub-Dog creature card with converted mana cost X or less from your hand onto the battlefield tapped.