Mirror Herb + Competitive + Multiple stat drops

[FredrIQ]

While browsing the PS code as an battle engine mechanics check in a personal project, I noticed something that didn't seem entirely right. I confirmed my suspicions with a friend who owned SV.

PS triggers Mirror Herb as a post-boost action. However, Competitive triggers after each boost and is itself a boost. This results in a problem. Tests were done with a Palafin holding Mirror Herb knowing Tickle against a Wigglytuff with the ability Competitive.

Showdown behaviour:

• Tickle is used.
• Tickle lowers Atk
• Competitive procs (+2 SAt)
• Mirror Herb procs (+2 SAt)
• Tickle lowers Def
• Competitive procs (+2 SAt)

Suspected, and confirmed in-game behaviour:

• Tickle is used.
• Tickle lowers Atk
• Competitive procs (+2 SAt)
• Tickle lowers Def
• Competitive procs (+2 SAt)
• Mirror Herb procs (+4 SAt)

[itsdarsh]

For myself when I tested in game, I tested with a Dondozo with Tickle holding Mirror Herb against a Bisharp with Defiant. Same behavior.