Pearl Lake Ancient — ruling 1

A spell or ability that counters spells can still target Pearl Lake Ancient. When one resolves, Pearl Lake Ancient won’t be countered, but any additional effects of that spell or ability will still happen.

Pearl Lake Ancient — ruling 2

Any spell you cast that doesn’t have the type creature will cause prowess to trigger. If a spell has multiple types, and one of those types is creature (such as an artifact creature), casting it won’t cause prowess to trigger. Playing a land also won’t cause prowess to trigger.

Pearl Lake Ancient — ruling 3

Prowess goes on the stack on top of the spell that caused it to trigger. It will resolve before that spell.

Pearl Lake Ancient — ruling 4

Once it triggers, prowess isn’t connected to the spell that caused it to trigger. If that spell is countered, prowess will still resolve.

Pearl Lake Ancient : règles, fonctionnement et interactions (MTG)

Pearl Lake Ancient is one of those cards players keep asking about. Here is, in plain words, what its official text says, the rulings published by Wizards of the Coast, and the combos players actually run.

Official card text

Flash This spell can't be countered. Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.) Return three lands you control to their owner's hand: Return this creature to its owner's hand.

How it works : Pearl Lake Ancient

Original English text — Wizards of the Coast / Scryfall

#1September 20, 2014· Wizards of the Coast
A spell or ability that counters spells can still target Pearl Lake Ancient. When one resolves, Pearl Lake Ancient won’t be countered, but any additional effects of that spell or ability will still happen.
No other card is named in this ruling.
#2September 20, 2014· Wizards of the Coast
Any spell you cast that doesn’t have the type creature will cause prowess to trigger. If a spell has multiple types, and one of those types is creature (such as an artifact creature), casting it won’t cause prowess to trigger. Playing a land also won’t cause prowess to trigger.
No other card is named in this ruling.
#3September 20, 2014· Wizards of the Coast
Prowess goes on the stack on top of the spell that caused it to trigger. It will resolve before that spell.
No other card is named in this ruling.
#4September 20, 2014· Wizards of the Coast
Once it triggers, prowess isn’t connected to the spell that caused it to trigger. If that spell is countered, prowess will still resolve.
No other card is named in this ruling.