Multi-Function Pocket Arcanometer

A large polished gold pocket watch with several knurled knobs and buttons around the edge and a very complicated dial that indicate all manner of things, including magical residue density, compass direction, illusionary entropy, the phase of the moon, leyline angle, and even time of day. It also comes with a strong chain for fastening it to your person.

The Arcanometer functions as an arcane focus, and while you hold it, you can cast the Guidance cantrip and the Detect Magic and Identify spells at will without requiring expensive material components.

The Arcanometer also has 10 charges, and it regains 2d4+2 charges when you finish a long rest. You can cast the following spells by spending charges: Alarm (1 charge), Gift of Alacrity (1 charge), Hold Person (2 charges), Locate Object (2 charges), Haste (3 charges), Slow (3 charges), Freedom of Movement (4 charges), Temporal Shunt (5 charges), Contingency (6 charges), Time Stop (9 charges).

You can also spend 3 charges to unwind time for a fraction of a second. As a reaction when you or another creature within 30 feet of you makes an attack roll, ability check, or a saving throw, you can force the creature to reroll. You make this decision after you see whether the roll succeeds or fails. The target must use the result of the second roll.

If you use the Arcanometer's final charge, roll a d20. On a 1, the watches' magic unravels, casting the Time Ravage spell on the user (DC 19). If the spell takes hold the watch becomes inoperable, except as an arcane focus, until the spell is ended or kills the user.