Final Fantasy Tactics Walkthrough

Take out an Archer and a Summoner as soon as you can and you'll only have to deal with one other Archer. The best way to win this battle is to stay on the outside and lure the Lancers out, because they'll give you a lot of trouble on the stairs, blocking your progress due to the narrow walkway. Lancers are easier to manage when they're out in the open, and if the only person left capable of attacking you is the random Monk and the other Archer, there won't be many other problems. Let the Monk come to you to avoid getting a subset of your battle group partitioned off from the rest.

A good way of taking out the Summoner is to jump and use Holy. If you have a Summoner of your own, try to hit both Lancers at once as they come closer, then get your melee troops ready. Keep someone around to heal with X-Potions because the enemies can hit pretty hard. Should the Lancers give you an opportunity, you might as well send a quick and far-moving character into the softer targets, assuming you can keep them alive long enough to do damage; this will split the enemy's focus considerably.

In the chaos that ensues, Dycedarg gets poisoned from the cloud which Balk recently spread, and Prince Larg is afflicted alongside. Seeing that the poison is not fatal, Dycedarg takes a further step and assassinates Larg (much to his brother Zalbag's surprise), then orders Zalbag to put the knife in one of the fallen soldiers' hands so that they can wash the scenario away as the actions of a low-ranking traitor.