Time Construct

Wondrous item, legendary

The time construct is a machine built by Cagoth-ze to gain access to the contents of the arcane scriptorium. Although Cagoth-ze is only a middling wizard, he’s something of a savant when it comes to theories of manipulating time.

The trouble with time machines is they’re difficult to test in anything but full scale. Cagoth-ze spent years refining his hypotheses and more years building the construct, but he couldn’t know for sure exactly what it would do until he installed the final energy crystal and sealed the last matrix. At that point, it was do or die. Either the construct would work, or it wouldn’t.

In this case, however, the machine both worked and didn’t. It didn’t bring the library from the distant future back to the present as Cagoth-ze intended it to. The magic of the elves anchoring the library to the future was much stronger than Cagoth-ze expected it to be. Instead, since the construct couldn’t bring the library backward, it went forward.

Cagoth-ze’s time construct is a living construct with (minimal) intelligence, not just a machine. It doesn’t follow a program; it responds to requests and built-in prerogatives in the best manner it can, according to its knowledge and understanding. In this case, it’s simply not capable of fulfilling the purpose for which it was built (overcoming the elves’ magic and shifting the entire arcane scriptorium to the present time), but it keeps trying. The way it tries is by following different temporal pathways from the present to 100,000 years in the future and back to the present again. The number of such potential pathways is literally limitless, so the construct will never stop until it succeeds (impossible), it’s destroyed, or its energy matrices can no longer maintain themselves from the currents of time. In this quest, the construct bounces through time essentially at random. Any creature within 30 feet of the construct when it cycles to a new time setting can be dragged along with it; the choice is up to the construct whether it includes or excludes a creature from its time field.

Although the construct has significant control over time, one rule it can’t violate is that its own internal clock is inextricably tied to its “present.” If it experiences three days of time passing while it’s jaunting through different eras, then when it returns to the “present,” three days have elapsed since its departure. The construct can’t jaunt a few seconds into its own past; not because that would create a paradox but because it’s simply incapable of doing so.

• Energy Storage. The construct has a limited supply of energy. Every so often, it must stop to recharge its energy matrices by siphoning vitality from the time continuum itself. Typically, this occurs after every 1d4 shifts to a different era. Each time the construct triggers its defensive field counts as one shift. It usually pauses to recharge while it has enough energy remaining for one shift, because shifting into an unknown time period with no reserve energy is a huge risk. Recharging takes 1d3 days.
• Defensive Field. The construct is not a weapon, and because Cagoth-ze didn’t foresee how dangerous its job would be, he didn’t build in any offensive capability. As soon as the construct started experiencing the dangers of the future, it reconfigured itself so it wouldn’t be defenseless. It can project an altered version of its time field to incapacitate creatures around it; it thinks of this effect as its time punch. When it triggers the time punch, every creature within 30 feet of the construct takes 8d8 radiant damage and is knocked unconscious for 1d4 hours. A successful DC 18 Constitution saving throw halves the damage and reduces the length of unconsciousness to minutes instead of hours.
• Survivability. The construct is destroyed by 25 points of damage. Its AC is 15. It is immune to necrotic, poison, psychic, and radiant damage, to all conditions, and to all damage from nonmagical weapons not made from adamantine. It makes saving throws and ability checks with a modifier of +9. Dispel magic cast at 9th level shuts the construct down temporarily, but it repairs itself and resumes operating after 1d6 hours. If the construct is destroyed, it stops working in whatever era it currently occupies and anyone with it is stranded; it doesn’t automatically return to the present. There’s no way for anyone other than Cagoth-ze to pause the construct’s jaunts through time (other than with dispel magic), to reason with it, to threaten it, or to ask it questions or request favors.