The way I looked at Even Match in FFXI was there was a 50/50 shot of winning. Meaning the mob is evenly matched against you.

Tough/Very Tough means it would be very tough for you to kill it

decent Challenge was a decent challenge to kill but should be doable.

Easy Prey was they would be easy for you to kill.


In FFXIV, I would say even match is a mob 10ranks above you