After visiting the Tomb of Horrors or the Temple of Moloch (or both), the characters should have recovered some of the missing components of the Infernal Machine. Whenever they return to their original time, Lynx and Sir Ursas both make a play for the components, desiring to use them to complete and control the Infernal Machine of Lum the Mad.
Special Delivery
Whichever agent the characters are working for, their mechanical guide is programmed to teleport them back to the agent’s manor. If the characters somehow obtained both mechanical guides, they can decide which agent they want to initially return to. (Even if the characters have done secret deals with both agents, they should choose one to be their initial contact upon their return to their original time.)
If the characters somehow manage to return to their original time at any other location, a courier arrives at that location shortly thereafter, delivering an urgent invitation to come to the manor to discuss the results of their expedition. If the characters have the intent of avoiding the agent, the agent comes to find them in short order, and arranges for their mechanical guide to teleport everyone back to the manor.
Formal Review
When the characters meet with their chosen agent, Lynx or Sir Ursas asks to inspect any missing components they’ve collected. The agent agrees to pay the characters as arranged, but only after their servants test that the components are in working order. The characters are then led to the agent’s workshop. As they go, the agent talks about deducting expenses for any resources used, damage to the mechanical guide, and so forth—in general, becoming increasingly insidious.
Completing the Machine
When the characters first see the workshop, they become aware of the scope of what the agent is hoping to achieve.
The entire workshop is filled with a massive magical-mechanical device, worked on by a half-dozen servants. With no visible means to move it, the Infernal Machine of Lum the Mad must presumably have the power to teleport itself from place to place. It appears ancient, the style of its crafting unlike anything you’ve ever seen before. It features some sixty levers, forty dials, and twenty massive switches, as well as a booth large enough to hold four humans—but whether those humans would be the machine’s operators or the targets for its magic is unknown.
When the components the characters collected are presented, the agent’s assistants (six Cultist in official-looking white lab coats) work quickly to install those components into the Infernal Machine. The mechanical guide that’s accompanied the characters attaches itself to the machine, allowing it to serve as a command unit.
Another six Cultist then appear with the agent’s secret prisoner to finalize the programming.
A door on the far side of the workshop opens, and six more assistants stride forth with a weary-looking prisoner in tow. A human male with a haughty bearing, and wearing tattered, once-regal clothes, the figure gazes up at the great machine with a sense of recognition and longing.
Your host laughs, gesturing toward the figure with a flourish. “Adventurers! May I present Lum the Mad!”
Lum the Mad
In response to any reaction or questions, the agent proudly explains how the partially functioning Infernal Machine was used to find and capture Lum the Mad, so that he could assist in restoring the machine to its primal state.
Lum uses the warlord stat block, but is unarmed and has no attacks while under guard. He possesses sufficient knowledge to program the Infernal Machine, allowing it to fully function according to its description now that the missing components have been restored. In his state of low-grade madness, Lum has no reason to not follow the agent’s orders and help bring the machine online. However, he is also able to deactivate the machine, or even cause it to self-destruct—if the characters can convince him to do so with appropriate roleplaying or Charisma checks of your determination.
Raid Against the Machine
Immediately after the missing components are installed and Lum is presented, the other agent launches a surprise raid against the first agent’s manor. Read the following, adding details as appropriate depending on whether Lynx or Sir Ursas is the one coming for the Infernal Machine, and whether or not the characters have met the other agent:
A sudden shattering crash is heard as the wall of the workshop collapses to rubble! A fighting force advances through a cloud of dust, led by a most unusual-looking figure.
The other agent arrives with a full complement of a dozen servants (use the cultist stat block).
During the raid, both agents attempt to attune to the Infernal Machine. You can decide which one is successful or allow chance to decide (see “Complications” below), taking into account the actions of the characters if they support one agent or the other.
During the fight, both agents shout out accusations that reveal the other’s true natures. Those natures are then confirmed by the agents themselves. Any injury dealt to Lynx Creatlach shows the unnatural construction of her undead flesh and the rune-scribed skeleton beneath it. Any injury dealt to Sir Ursas causes him to shout out in rage, swearing vengeance “in the name of my unholy patron, Bel!”
If either agent gains control of the Infernal Machine, they immediately use it to attempt to defeat their rival. (The machine has all its normal functions except its
Complications
During the raid, any number of complications might arise. As desired, you can roll on the Machine Fight Complications table (see the next page) at the end of each round of combat, rerolling or ignoring results that have already occurred.
Failure Is an Option
If the characters failed to recover a significant number of components from either site in the past—and assuming you don’t want to send them back—you can work that into this final showdown. Whichever agent the characters return to is disappointed in their progress, but comes up with an alternative plan. Knowing that the other agent might also have sent their own operatives back to collect the missing components, the characters' agent invites them to help break into the rival agent’s workshop to steal those components from the rival’s version of the Infernal Machine. Reverse the general setup of this section to have the characters on the side that breaks into the workshop. There, they see the rival agent holding Lum the Mad, and in the process of completing the Infernal Machine.
Machine Fight Complications
| d100 | Result |
|---|---|
| 01–15 | Lynx attunes to the Infernal Machine and begins to use its powers. |
| 16–30 | |
| 31–45 | Lum is threatened by cultists of one agent or the other. If aided, he agrees to work with the characters in whatever fashion they desire. |
| 46–55 | The Infernal Machine comes to life, summoning a CR 5 monster (your choice) that attacks the creatures closest to it. |
| 56–65 | The Infernal Machine comes to life, summoning a CR 10 monster (your choice) that attacks the creatures closest to it. |
| 66–70 | A spellcaster fighting for Lynx casts a |
| 71–75 | A spellcaster fighting for Sir Ursas casts a |
| 76–80 | Lynx slays Sir Ursas. She cuts off his bear paw, promising to turn it into her personal backscratcher. |
| 81–85 | Sir Ursas slays Lynx. He tears her flesh golem suit away to reveal the skeleton within, which he then shatters. Lynx’s skull might still remain animated and conversational. |
| 86–90 | Both Lynx and Sir Ursas manage to slay one another simultaneously. |
| 91–00 | Both Lynx and Sir Ursas decide that events have grown too heated and escape into the city. High bounties are set for their capture. |
Concluding the Adventure
Depending on the hook you used and how this adventure fits into your overall campaign, a number of things can happen at the end of Infernal Machine Rebuild.
Nine Hells or Bust
If either agent is successful in taking the Infernal Machine of Lum the Mad to the Nine Hells, it changes the balance of power in Avernus. Either Zariel is able to solidify her rule of that level, or Bel is able to reclaim the level using the machine’s power. What happens as a result is entirely up to you, and might come into play if you are running Baldur’s Gate: Descent into Avernus as part of your campaign.
Finders Keepers
If the characters plan on keeping the missing Infernal Machine components for themselves, for delivery to another patron (such as Kwalish), or simply to keep them out of the hands of the agents, both Lynx and Sir Ursas launch separate attacks to recover them. These attacks can either be spaced out to avoid overwhelming the characters, or you can have both agents attack at the same time and largely concentrate on each other.
Our Infernal Machine
If one or both of Lynx and Sir Ursas are defeated, the characters might end up in possession of the Infernal Machine. If you opt to keep this powerful artifact in your campaign, see appendix C for its statistics. Otherwise, you can decide that the machine has been fatally programmed to disperse its components to all-new locations—but only after the characters have had a bit of time to experiment with it.
Of course, if the characters take possession of the machine for any length of time, any surviving agents seek revenge against them. Likewise, so will the agents' patron archdevils, Zariel and Bel, who might send forces of cultists to finish the characters off.
Mechanical Guides
The mechanical guides are programmed to serve their agent masters—and to self-destruct in the event that anyone else attempts to take control of them. Still, exposure to the power of the components of the Infernal Machine might change a guide’s programming, allowing the characters to befriend and permanently claim it as a companion or ally. If this happens, a guide’s time traveling ability can be curtailed as you desire.
The Joys of Time Travel
Because this adventure traverses both time and space, you might decide that actions carried out by the characters in the past of chapters 3 and 4 create changes in the present of the campaign world when they return. For example, the construction of the Tomb of Horrors might be disrupted, in which case it holds less prominence in later times. If Thessalar regains his missing sculptors, he might complete his stone golem and send it out to destroy Moghadam and demolish the tomb while it’s under construction. Thessalar might also create more monsters than he is already known for, which can spread throughout the world.
Feel free to keep track of what events and choices in the past might have future implications—and have fun presenting the fallout of those events to your players!