How does the Irressitible Faefolk work? Is my opponent the attacker or am I the attacker?

When you play Irresistible Faefolk and use its ability to move an enemy unit to the battlefield it just entered, the determination of who is the attacker and who is the defender depends on who applied the "Contested" status to that battlefield first.

According to RiftJudge FAQ #5394, #2345, and #7275, the player who controls the unit that applies the "Contested" status is the attacker.

How it works:

1. You move Irresistible Faefolk: When you move Irresistible Faefolk to a battlefield, if that battlefield was previously empty or uncontrolled, you apply the "Contested" status to it. You are the attacker.
2. You use the ability: You trigger Irresistible Faefolk's ability to move an enemy unit to that same battlefield.
3. Combat designation: Because you were the one who applied the "Contested" status to the battlefield first, you remain the attacker and your opponent is the defender, even though you moved their unit into the combat.

Important Nuance: If you move Irresistible Faefolk into a battlefield that was already contested by your opponent, your opponent is already the attacker. Moving their unit to that battlefield does not change the attacker/defender designations; your opponent remains the attacker.

This is my interpretation based on the established rules for Contested status and combat designation. No official FAQ exists for this specific card, but it follows the same mechanics as cards like Charm (see RiftJudge FAQ #5394, #2345, and #7275).