I thought it was pretty simple.
the red vs blue was done in a less in your face attitude, it was intense, you fought numerous times, it was very personal, it was a great rivalry.
Cloud vs Sephiroth was convoluted, involved jenova a great deal, was alot of chasing and really, and really everyone in the party had motivations to stop him, it wasn't a great rivalry.
It says nothing about either game. Doesn't mean one is worse or better. I feel like Cloud's party vs the turks was a better rivalry, but the contest was 1 on 1, not group vs group.
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Evil_Gogeta: You... you quoted yourself in your sig?