If Metallic Mimic and a creature of the chosen type enter the battlefield at the same time, the system will incorrectly give that creature a +1/+1 counter

[stash86]

What is the expected behaviour of the card?

• That creature won't get the counter because they enter the battlefield at the same time, hence metallic mimic's effect wouldn't be able to see that creature ETB

What is the actual behaviour of the card?

• The creature will get the +1/+1 counter

Screenshot

Please provide a list of affected cards
Affects: [Metallic Mimic]

Card Images

[stash86]

Official ruling from Gatherer
2/9/2017 Creatures of the chosen type that enter the battlefield at the same time as Metallic Mimic won’t enter with an additional +1/+1 counter.