Wild Arms 2 [85] - Xenonblade Chronicles

The final three of the "regular" optional bosses and the rundown of how to fight them.
Zavorg at the Meteorite Crater: Uses Darkness, is weak to Darkness, and tends to waste his turns. But also has crazy magic evasion so use a physical team. One of the easier ones overall.
Zolinge at Wind Tiger's Den: Put up Instant Death protection and smash it with Earth.
Xenon at Slayheim Castle: The one that could be a contender for "superboss." Start off with Light Rings equipped until Lilka can cast Field on everyone, then switch to Darkness Rings and hit it with Darkness attacks. It will go down eventually.
And all those are still somewhat pieces of cake compared to the final two...
Thumbnail art of Channel Mascot Dyana as Lilka by / elfudraws