If you’re familiar with 4th edition (and frankly if you’re not why come to this site, 95% of the posts in the last 18 months have been about 4th Edition Dungeons and Dragons) then you know that Solo creatures, the Big Bad Evil Guy or Big Boss of fights for any particular level in 4th Edition really don’t work well Solo.
[Note: This has all be hashed out before but someone asked about it so here's my take]
While Solo creatures are designed so they cost the same XP as 4 standard creatures, they don’t really have 4 times the firepower or stamina.
Four standard creatures get 4 attack rolls at least on the opening round. A solo gets two typically or at least most have a ‘double attack’ of some kind that lets them target two creatures or get two hits on one.
Four standard creatures have sets of hitpoints that typically have 2 or more of them being worn down each turn. A single solo has one set of hitpoints that everyone is wearing down each turn.
Solo’s typically have AOE’s of some kind and a lot more powers but they’re still limited to one turn per round. Â Four standards get four turns per round.
So the key thing to take away from this is that solo’s shouldn’t be fought solo as a result as a general rule. There should be other game elements arrayed against the players to keep the fight interesting for them or the solo itself should be intrinsically interesting.
Another option that I’ve found that works well is not have your boss fight be a solo but instead toss in a two or more elites as your solo. I recently used this to good effect, using level 5 elites as a boss fight against 5 level 1 characters (my HR make this more viable than the standard system). As the party eliminates each elite from the fight they get a sense of accomplishment greather than the grinding away at the bag of HP that a solo grants IMO.
As a DM one thing you can do to help you have a more dynamic challenge is have additional elements introduced during the combat.
Examples of this using The Mummy -
A solo mummy is released from its tomb by foolish delvers. As they array themselves to attack it, it screams out words of ancient magics and lesser mummies burst forth from their burial pits throughout the complex and head toward the main chamber. You can tailor the waves of low standards or minion creatures as your party needs them. Getting close to a TPK? tone down the waves in quality and quantity. Players are kicking your bosses ass? Then toss in some extra waves or have more than one wave attack at the same time.
I had a ‘boss construct’ encounter planned for my last session but pulled it to save for another time as it would have likely resulted in a TPK as the party was out of healing abilities and low on surges. My plan was a giant construct guardian. In the area as well I had plans for turrets that fired tanglefoot material. The boss was designed so that at bloodied it would break into three individual constructs, each with additional abilities that the main version didn’t have. Â Between the constant harassment of the being immobilized from the turrets and the creature’s arms and shoulders breaking away to create skittering skirmishers while the main torso turned into a brute would have I believe made for a pretty good boss fight. I’m going to rewrite this for another encounter later on though.
A dragon encounter with lots of kobold minions including lots of traps in the area laid by kobold trapmasters could be another exciting solo fight.
What you really want to avoid are constant slugfests or ‘flintstone boxing’ where the players surround the solo and each just pounds away at the other until the players win or you destroy them. Sure a stand-up brutefest is fine occasionally but 4th Edition has so much potential for interesting fights. But that’s potential that you as the DM have to fulfill, the system won’t do it for you.
So toss in ice flows or mud pits, cables to swing on, crumbling bridges and ledges, falling rocks, lurkers joining the fight halfway through, bosses that summon or morph into something else. Add in turrets or fighting while falling down a volcano. Add one really LONG fight where the it becomes a boss fight overall but the players are forced to fight group after group of weak creatures without the ability to take a rest.
Mix it up, have fewer fights but ones that are more interesting rather than more fights but boring ones. Quality over quantity goes hand in hand with 4th Edition fights.