Memerai's chamber

Memerai's chamber enters the battlefield with
five etherium counters on it.
Whenever you draw one or more cards, put an etherium counter on Memerai's chamber.
Whenever there are thirteen or more etherium counters on Memerai's chamber, sacrafice it.
Then put an X/X artifact creature token where
X was the number of etherium counters on
Memerai's chamber.