Do attack boosts affect the power of Foul Play?

Question

One time, I OHKOed a Garchomp with a Thundurus-T using Foul Play. The garchomp had +4 attack from Swords Dance And Swagger. Did the boosts affect the OHKO?

Answer 1

It does actually. Swagger+Foul Play is a strategy used by some players to wear down the opponent fast and take minimal damage. This technique is called "SwagPlay" and its banning is being suspected in OU.

Foul Play inflicts damage. It uses the target's Attack stat to calculate damage, as opposed to the user's Attack stat. The target's Attack stat modifier is incorporated into damage calculation. With the exception of the Attack stat and Attack stat modifier, all other factors affecting damage calculation, including the item, Ability, type, and status ailment of the user of Foul Play, are incorporated as normal. If the user has the ability Huge Power or Pure Power, Foul Play will be calculated with double the target's attack stat.

Source: Experience and Bulbapedia's page on the move, Foul Play.

Answer 2

Yes.
Foul Plays damage differs from the attack. Garchomp also got high attack.

Source I use Swagger + Foul Play for my Klefki all the time

Answer 3

Yes, it does boost the power of Foul play.

>The target's Attack stat modifier is incorporated into damage calculation. With the exception of the Attack stat and Attack stat modifier, all other factors affecting damage calculation, including the item, Ability, type, and status ailment of the user of Foul Play, are incorporated as normal.

Source: Experience and Bulbapedia

Hope I helped.