When you go to plains to meet the Grasslanders
for a peace treaty, they suddenly attack. You
will be taken to a major battle. Defeat all the
enemies instead of retreating as instructed. If
you defeat all enemies, proceed to the location
where you were supposed to retreat. The battle
will end. Chris, Salome, Borus, and Roland will
all gain two levels. On Amur Plains after the
battle, unequip your armor and let yourself be
killed. Do not proceed to Karaya Village. When
asked to give up, select "No Way". You will
return to last save point, but still will have
the two levels gained for everyone. Return to
the major battle and repeat.