How does Progenitor Mimic work?

Progenitor Mimic copies exactly what was printed on the original creature and nothing more (unless that creature is copying something else or is a token). If the chosen creature is a token, Progenitor Mimic copies the original characteristics of that token as stated by the effect that put it onto the battlefield.

Does Progenitor Mimic target?

Progenitor Mimic states that it enters the battlefield as a copy of any creature on the battlefield, but doesn’t say copy “target” creature.

Is a triggered ability an activated ability?

Unlike activated abilities, triggered abilities do not need to be activated, — they trigger regardless of players’ wishes and are subject to no limitations. 603.2a. Because they aren’t cast or activated, triggered abilities can trigger even when it isn’t legal to cast spells and activate abilities.

What is a triggered ability magic?

A triggered ability is an ability that automatically does something when a certain event occurs or a set of conditions is met (the latter is called a state-triggered ability).

Can Progenitor Mimic copy a legendary creature?

If a Progenitor Mimic copies a legendary creature, then each time its triggered ability resolves and you get a token copy of the creature, you have to choose to keep either the token or the Progenitor Mimic copy, and you put the other into your graveyard.

Does Progenitor Mimic copy counters?

No, counters are not copied. The Progenitor Mimic, when copying a Nimbus Swimmer, would enter the battlefield as a 0/0 creature and immediately go to the graveyard.

Does countering an ability destroy the card?

Hope is free. Countering an ability of a permanent (such as with Disallow) doesn’t destroy that permanent (all it does is remove that ability from the stack [C.R. 701.5a]); if a spell does more than counter that ability it will say so (examples are Interdict and Teferi’s Response).