Thesnut, Gnome's Friend

When Thesnut, Gnome's Friend enters the battlefield, create a Legendary Equipment
Artifact named, "Gnome Shield" with
"Equipped creature gets +0/+2 for each Gnome
you control and +2/+0 for each Halfing you
control", and "Equip {3}".
At the beginning of each opponent's end step,
create a 0/2 green Gnome creature token.
Then, if you control more than three Gnomes,
transform Thesnut.