Predatory Advantage — ruling 1

Predatory Advantage’s ability has an “intervening ‘if’ clause.” That means (1) the ability won’t trigger at all unless the opponent whose turn it is didn’t cast a creature spell that turn, and (2) the ability will do nothing unless the opponent whose turn it is still hasn’t cast a creature spell by the time it resolves.

Predatory Advantage — ruling 2

Predatory Advantage checks whether a player cast a creature spell, not whether a creature entered the battlefield under that player’s control. If that player cast a creature spell but you countered it, for example, you won’t get a Lizard token that turn.

Predatory Advantage — ruling 3

In a Two-Headed Giant game, Predatory Advantage’s ability triggers twice at the end of the opposing team’s turn: once for each player. If neither of those players cast a creature spell that turn, you’ll get two Lizards. If one of those players cast a creature spell but the other didn’t, you’ll get one Lizard.

Predatory Advantage : règles, fonctionnement et interactions (MTG)

Predatory Advantage 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

At the beginning of each opponent's end step, if that player didn't cast a creature spell this turn, create a 2/2 green Lizard creature token.

How it works : Predatory Advantage

Original English text — Wizards of the Coast / Scryfall

#1May 1, 2009· Wizards of the Coast
Predatory Advantage’s ability has an “intervening ‘if’ clause.” That means (1) the ability won’t trigger at all unless the opponent whose turn it is didn’t cast a creature spell that turn, and (2) the ability will do nothing unless the opponent whose turn it is still hasn’t cast a creature spell by the time it resolves.
No other card is named in this ruling.
#2May 1, 2009· Wizards of the Coast
Predatory Advantage checks whether a player cast a creature spell, not whether a creature entered the battlefield under that player’s control. If that player cast a creature spell but you countered it, for example, you won’t get a Lizard token that turn.
Card named in this ruling
Lizard
#3May 1, 2009· Wizards of the Coast
In a Two-Headed Giant game, Predatory Advantage’s ability triggers twice at the end of the opposing team’s turn: once for each player. If neither of those players cast a creature spell that turn, you’ll get two Lizards. If one of those players cast a creature spell but the other didn’t, you’ll get one Lizard.
Card named in this ruling
Lizard