Boots of Haste

The Boots of Haste (not to be confused with the Dungeons and Dragons 5th Edition Boots of Speed) are an item that can be clicked together with a Bonus Action to cast the Haste spell on the wearer. They require attunement.

Properties
The Boots of Haste in Critical Role are a combination of the Boots of Speed from D&D 5e and the corresponding Boots of Speed from Pathfinder. Vax's boots follow the D&D rules for activation, but have the Pathfinder effect of casting Haste. Based on that, they would have the following properties:

''Requires Attunement While you wear these boots, you can use a Bonus Action and click the boots' heels together. If you do, you benefit from the effects of the Haste spell for the duration of this effect. If you click your heels together again, you end the effect. When the boots' property has been used for a total of 10 minutes, the magic ceases to function until you finish a Long Rest.''

Note that, unlike the actual Haste spell, the boots' effect does not require concentration and does not cause lethargy after use.

Campaign One: Vox Machina
Vax'ildan owns a pair of these boots that have caused a long-standing competition between him and his sister, Vex'ahlia.
 * Vex first tried on the Boots of Haste for the fight with Umbrasyl in . She was reluctant to return the Boots when Vax demanded them in, but he said he'd just steal them overnight if she refused, and she relented.
 * Vax again lent the Boots of Haste to his sister in, and in when he requested them back and he argued he could get more out of them, she gave him some sass before assenting.
 * Vex claimed the Boots from a disintegrated Vax, and when he miraculously returned a short time later, she initially refused to give them back despite his guilting her and she used them in a critical race against time in Elysium, but soon took pity on him and returned them.

Following a frustrating fight with Vorugal and Yenk and a prior battle with Saundor in which Grog had trouble reaching the party's enemies, a conversation between Vex and Grog seemed calculated to make Vax feel guilty about not giving Grog at least one of his three extremely powerful mobility-enhancing items: the Boots (bonus action to gain, for one minute, double movement speed and an extra action each turn that can be used to Dash or Disengage), Deathwalker's Ward (bonus action to gain a 60-foot flying speed for one hour), and now Whisper (effectively granting a 60-foot teleportation once per turn).

Trivia

 * CritRoleStats has examined which of the twins actually gets the bigger benefit from these boots in Who Wore It Better: Boots of Haste.
 * Matthew Mercer has stated that the Boots of Haste are a holdover from the Pathfinder campaign, and were designed before he truly understood the "action economy" of D&D 5e. He has also made suggestions as to how they could be better balanced. Suggestions included adding a Concentration requirement, adding an effect consistent with the lethargy after Haste wears off, or only letting the effect last for 1d4+1 rounds.