Forcas III

From Memory Alpha, the free Star Trek reference.

Forcas III is the third planet in the Forcas system, in the Klingon Empire.

Worf entered a bat'leth competition here in 2370, and won Champion Standing. (TNG: "Parallels")

In that episode, Worf experienced multiple quantum realities, in some of which his results at the competition, and even his attendence, were different.

Forcas III is also where a drink Data described as "revolting" came from. (Star Trek Generations)