In World of Warcraft, probably every usage of FTW means "For The Win". Elsewhere, FTW could have other meanings. See below for other definitions. Essentially, for the win means that an event or a weapon or talent or skill, etc., is favorable and important. As with any other term, it can be used sarcastically, as in "a real winner."

Examples

• Pally bubble ftw → "the bubble is what saved me"
• Thunderfury FTW → "nothing beats Thunderfury"
• LD ftw → "it's always fun to be dropped from server"

External links

Wikipedia 

Acronymfinder.com What does FTW stand for?

Forum post from  Atomicmpc.com FTW: The most annoying acronym ever?

Urbandictionary.com Definition