I'm curious about your definition of "killed" here.
If it means dead according to the rules, it won't work very often, since not many level-appropriate opponents will go from positive HP to negative bloodied value just from that attack. I guess if she has living minions of her own that get caught in it they'll get zombified, but that's about it.
If it means dying (0 or negative HP) then it's way too powerful, since it would take away unconscious characters' ability to rejoin the fight.
It means dead, DED, dead, as in negative bloodied value. That specific clause of the power is unlikely to be significant and I knew that going in, but would still make for an interesting change to the fight if it did happen, so I decided to include it.
The fight with this solo ran really well. The monster wasn't a pushover, but she didn't TPK the party. Healing was required and our leader was plenty busy, a few action points were spent, and a few dailies were used, in short the PCs were challenged but not overwhelmed. The fight was consistently interesting throughout the encounter, and the encounter concluded in the fifth round just as the PCs were expending their last encounter powers. This also means we avoided the situation some have complained about where the fight drags on with PCs down to just their at will attacks still trying to slog through the massive hp pool of a Monster you've only just bloodied. Also the encounter was tactically dynamic throughout, the monster and the PCs were consistently moving and repositioning to try to gain advantage over one another. It was great and I'm very proud of the encounter.
Since I think the encounter went so well, I want to try to share the process I used to write this solo in a way that would keep the encounter interesting and challenge my PCs.
When I'm going to design a solo, I start out the same way I approach designing regular monsters: by determining a monster concept. Once you know the monster concept you can determine the monster's role, and from there you can derive the monsters stats.
As an example lets look at the solo I just ran for my PCs in our session on Friday: Jaxia, the Corpse Bride of Acererak. The campaign I'm currently running is set in a world beset by an army of undead conquerors where hostilities have recently broken out again after two decades of relative peace. My PCs have been fighting the undead menace since first level and are now most of the way through the heroic tier.
Currently my PCs find themselves in my own re-imagining of the tomb of horrors, the lair of the lich Acererak. In my setting Acererak fills the role of Undead bio-weapons engineer for the conquering undead army by turning his arcane research towards creating new and powerful undead. The tomb of horrors is one of Acererak's laboratories, filled with his creations (in addition to the traps and puzzles that made the original tomb of horrors so infamous). In this particular laboratory Acererak was experimenting on extraplanar creatures giving rise to fiery and icy undead from the elemental chaos, and powerful ghosts tainted by the energies of the abyss. During the planning stage of the adventure I knew I wanted to include some Fey undead, so this solo seemed like a opportunity to do that.
So at this point all I knew about my monster was that it would be a solo undead of Fey origin. I thought for a while that I might use the old "Bride of
Frankenstein" motif, but ruled that out after a few minutes. Acererak is heartless, cold, he cares only about researching that next spell or turning kittens into killing machines of undeath, in short he's not the marrying type. I still liked the image of the undead bride though, and would have to work it in somewhere. Perhaps before Acererak's experiments she was a powerful Fey who he kidnapped on her wedding day before her first dance with her new husband. That dance that was stolen from her became a focal point for her as she was twisted by Acererak's experiments and slowly driven mad.
For some reason at this point the words "Yes, she always did love to dance" popped into my head and served as a lightning rod for the rest of the design process. For those of you who recognize the quote you can probably see where I'm going, for those of you who haven't go out and rent yourself Joss Whedon's television series "Firefly" and the subsequent movie "Serenity" they're well worth seeing. I found myself remembering the barfight scene from early in Serenity and thinking "That's how the corpse bride fights: weaving through the fray delivering powerful kicks that down men twice her size." Which meant she was a skirmisher.
With a concept and a role outlined I could calculate the derived statistics. I decided on a level for my solo at this point, in this case since my PCs were going to be level seven when they reached this encounter I settled on level ten. Statistics like hp, bloodied value, and defenses were then derived. I used the baseline from DMG page 184 and then adjusted to suit my tastes and concept.
Jaxia, The Corpse Bride of Acererak
Level 10 Solo Skirmisher
Medium Fey Humanoid (Undead)
Initiative +12 Senses Perception +10; Darkvision
HP 358 Bloodied 179
AC 24 Fortitude 20 Reflex 26 Will 24
Resist Necrotic 10 Vulnerable Radiant 5
Saving Throws +5
Speed 6
Action Points 2
After the basics were nailed down it was time to think about powers. Powers are the most important part of monster design, they tell you what the monster can do. Power design is especially important for solo monsters since they will face the party alone.
Before continuing to delve into power design it would be useful to talk about one of my fundamental design philosophies. For me D&D has always been, and fourth edition more so than any of its predecessors, about an economy of actions. Whoever can do more has the edge. While the xp budget is one great tool for evaluating encounter balance, I also make sure to consider the action ratio when evaluating an encounter. In fourth edition most significant effects are the result of standard actions, so the simplest example of the action ratio looks like this Y:X where Y is the number of standard actions available to monsters and X is the number of standard actions available to PCs. This action ratio clearly illustrates the problem with Solos. I have six PCs in my party which means my solo starts at a significantly disadvantaged position of 1:6 in the action ratio.
In order to make this a balanced fight, I needed to equalize the action ratio, and if I wanted it to be a challenging fight I'd need to tip the action ratio in the solo's favor. Clearly I had some work to do. This work was accomplished by maximizing the monster's actions which increases the left side of the action ratio, and mitigating the PC's actions, which decreases the right side of the action ratio.
Enlightened with knowledge of the action ratio I returned to designing monster powers. I know that I need to shore up the left side of that action ratio, so I think about what types of actions there are: Standard, Move, Minor, Free, and Immediate. I'll want to use all of them if I'm going to get into balance, in fact I need to make most of them the equivalent of a PC standard action or more.
Standard actions are your bread and butter (or rice and bean, or fish and rice, or whatever other culturally significant staple food analogy you like) powers, so they're as good a place to start as any. All monsters have a melee basic attack. I've envisioned Juxia dancing about and kicking people so she'll get a Kick melee basic attack:
Kick (Standard; at-will)
m; +15 vs. AC; 2d6+5
Which brings the action ratio to 1:6, well no improvement there, but very few monsters have a melee basic attack as their only standard action power. I need to add another. I start flipping through the monster manual the way a mechanic trying to restore some cherry muscle car might look through a parts catalog. Does Jaxia need a four barrel carburetor, or high end brake rotors? I pay particular attention to the powers of existing solos to see how they attempt to close the action ratio gap. Multi attack powers are a common two for one action equalizer so I decide to throw one in. Since Jaxia is a skirmisher I also decide the power should have some baked in movement, and since I want to keep to the story that she's a powerful Fey I decide that movement should be teleporting:
Dance of the dead (Standard, at-will)
Jaxia teleports three squares and makes a Kick attack, then teleports three additional squares and makes a second Kick attack.
Ok, dance of the dead does in one standard action what would take most monsters two standard actions to do. Action ratio 2:6. I've started making progress on the action ratio front but I still have a long way to go. I could give Jaxia more standard action powers, but since Jaxia can only take one action of each type per turn (unless she spends an action point) I only count the most efficient use of a given action towards the action ratio. At this point I decide that I'm done with standard action powers, at least for now, I may revisit them when I have a more complete picture of my monster and where the action ratio ends up.
If I keep going down the list Move actions are the next logical choice, so that's what I think about next. Move actions are interesting. One of the improvements I really like about fourth edition is the clarification of the move action and what its for; movement and movement only. This means that it can't replicate a standard action, and thererfore cannot effect the action ratio. Does this mean that solos don't need interesting move action powers? Looking through the monster manual it would seem someone thought so, since few solos have interesting move action powers. One common complaint I've heard about solos is that they're not tactically interesting, that the fight devolves into a beat down with the PCs clustered around a stationary monster trading blows round after round. To which I respond: BORING! So I give all my solos and especially my Solo skirmishers interesting powers that use as their move action. In Jaxia's case I've already established that he's a teleporter, so she should have a teleport movement power. Just a teleport would be ok, but I want to do more to keep the encounter interesting so I decide to give Jaxia a power that teleports her one distance and teleports an adjacent enemy another, this will ensure there's lots of movement during the encounter. Which is how I came up with:
Feywild Two Step (Move; at-will)
Jaxia teleports 5 squares, and one adjacent enemy is teleported three squares, this action may not teleport an enemy into hazardous terrain.
I also make sure to add a note to Jaxia's speed entry to see also this power.
So I've defined Jaxia's Standard and move actions and at this point the action ratio is sitting at 2:6, with minor and immediate actions left to define. In order to swing this far enough to achieve balance we're going to need to make sure that each of these actions effects both sides of the action ratio. Since I don't have any particular minor actions in mind I go back to my parts catalog, and flip through the monster manual looking for powers that will swing both sides of the action ratio. In hopes of finding things that fit my flavor I pay close attention to Fey and Undead powers, one in particular catches my eye: the Unicorn's Fey Beguiling power. Fey beguiling is perfect because it takes a PC out of the fight, and what's more turns the PCs into Jaxia's unwitting ally. Typically Fey Beguiling is a standard action, but as I've already said, solos need to get a standard actions milage out of their minor action, so I just down grade it and slap it on the page.
Fey Beguiling (Minor, recharges when no creature is affected by the power) Charm
Ranged 5; +13 vs Will; the target cannot attack Jaxia, and the target must make opportunity attacks with a +2 bonus against any creature within reach that attacks Jaxia (save ends).
Action ratio check time: 3:5. Not bad. Jaxia still has no way to spend her immediate action, so I've one last chance to bring this fight into balance, but only if that immediate action swings both sides of the ratio. Lots of monsters have some kind of "Human Shield" ability, the Hobgoblin Strangler, and the Choker just to name a few. These are an example of an ability that turns the PCs actions aganist them thereby swinging both sides of the action ratio. So I decide Jaxia needs some kind of human shield. I already know that she teleports a lot, so I decide some kind of switch places with a PC and change the target of the attack will be cool. So I decide on Baleful Transposition:
Baleful Transposition (Immediate Interrupt, when Jaxia is targeted by a ranged attack, at-will)
Ranged 10; +13 vs. Will; Jaxia and the target teleport into one another's spaces and the target becomes the target of the triggering attack. Jaxia and the target must occupy the same space or the power fails.
Action ratio 4:4, balence achieved! Hold on a second thought, didn't I want this to be a challenging fight for the PCs, not a just a fair fight? I did, but I'm out of actions to give the monster. Well there are still free actions, however free actions can easily make a monster too powerful unless their strictly controlled by trigger conditions such as "When first bloodied" or "When an adjacent enemy falls to 0 hp." I decide to add a couple of those:
Dirge for the Dying (Free, when an adjacent enemy falls to 0 hp, encounter)
Close burst 3; targets living creatures; +13 vs. Will; 3d6+5 psychic damage. Any creature killed by this attack rises as a Zombie Rotter of its level on its next turn. Deafened creatures are immune.
Last Dance (Free, when first bloodied, encounter)
Jaxia makes two Dance of the dead attacks.
These kinds of triggered free actions can nudge the action ratio a little bit, but since they don't happen every round their effect is small. Oftentimes this small swing is enough to tip the action ratio slightly in the monster's favor delivering the challengeing fight the DM wants, however in this case I want to push my PCs a bit more than that.
This is where my other favorite element of fourth edition comes into play, exception based design. The rules say creatures get a single immediate action per round, and that's usually the case, however if I want a monster to have a second immediate action I can do that easily by putting an entry in that monster's stat block that states as much. Simple, elegant, wondeful, I love it!
Speed of the Dead
Jaxia may take two immediate actions per round
This means she could use Baleful transposition twice which gets the action ratio precisely to where I want it: 5:3. Of course currently Jaxia has only one option for each action type, which would contribute to a boring encounter where the monster did the same thing every turn. To solve this I need to introduce other options for some of her action types. I could use additional acitons with recharge times which would increase the variability of tactics, but in this case I chose to go with another immediate action option:
Song of Sickness (Immediate Interrupt, when Jaxia is target by a melee attack, at-will)
M; +13 vs. Fort; The target takes 1d8+5 necrotic damage and is weakened until the end of its next turn. Deafened creatures are immune.
I hope this illustruation of my process and design philosophy is helpful to others composing their own solos or looking to spice up existing solos to make them more interesting and credible threats on their own, since currently a lot of Monster Manual solos fall flat on their face.
. I haven't gotten around to making any of my own monsters but enjoyed reading how you broke yours down.
