Best practices for balancing separate enemies in an encounter?

Question

I'd like to run a game where a Mage has killed a necromancer, who has re-animated himself and is after the mage. The mage himself is evil. The necromancer makes up the majority of the session. The Mage is involved in an over arching plot I'm developing (and as such has a well defined character that means he wouldn't get involved with the party until the end).

How can I have two separate enemies in a game that are both opposed to the party, as well as each other? I can see multiple issues with this, such as making the party just watch the fight as well as splitting up the party and making them too weak to fight their opponents.

Has anyone done this? What best practices have you discovered?

Answer 1

The most important thing to keep in mind is that neither the mage nor the necromancer will want to let the other get the upper hand. If they each view each other as more of a threat than the party, they will try to eliminate each other first. Basically, the only reason they should ever appear to "team up" is if they fear that they are both equally powerful, but much weaker than the party. In active fights against multiple enemies, most participants will try and eliminate the biggest threat. Taking out the weakest first is only a viable strategy when the stronger guys aren't bearing down on you.

If it appears to be an all-around equal fight, (party vs. mage vs. necromancer,) then I would suggest trying to get the party to split up to take on each NPC. Since they are both casters, they should be preoccupied holding off the PCs immediately in front of them, but occasionally send some sort of area-affect spell towards the other fight, engulfing both other party members and their opposing NPC.

Also, since they are both casters, make good use of summoned monsters. This way, they can each have a physical presence in any smaller fights that may break out. Perhaps each NPC could summon a monster to protect their own flank, and a monster to attack the other NPC. The fight would look like this, then: An NPC fighting along side their summoned monster against half the PCs and the other NPC's monster, and a mirror fight on the other side.

Another option is to try and use the PCs as weapons of the NPCs, if the NPCs are powerful enough. Use compulsion effects to turn the PCs against each other (more difficult) or persuade them to change their attacks from one NPC to another (easier to do). Don't over do this, as PCs don't like being told what to do, but keep it in mind as a way to swing the balance of the fight.

Lastly, I would suggest making the PCs think that they could not take out one of the NPCs by themselves (even if this may not be true.) If they think they could, they will be more likely to focus on one NPC, and while it may be an efficient tactic, it will ruin the feel of the 1v1v1 fight.

Answer 2

My suggestion would be to make the party meet both of them separately and make sure that the PCs win their enmity and respect (that is, make them respect the PCs' abilities enough to take them as a threat to them as great the other guy). Then you have a 3-way battle... make the two antagonists focus on attacking the one they consider to be the greatest threat, maybe if one of them sees that he can't take on one side by himself and things get desperate he'd be willing to make a temporal alliance with the other one side, an alliance that should be betrayed as soon as the enemy is not as big a threat as the "ally". This will make for a pretty dynamic and even fight, but the PCs would have the edge by being more than one person (and therefore able to do many things at the same time)