Dancing Item

Large Construct, Unaligned

STR
18 (+4)
DEX
14 (+2)
CON
16 (+3)
INT
4 (-3)
WIS
10 (+0)
CHA
6 (-2)
Immutable Form.

The item is immune to any spell or effect that would alter its form.

Irrepressible Dance.

When any creature starts its turn within 10 feet of the item, the item can increase or decrease (your choice) the walking speed of that creature by 10 feet until the end of the turn, provided the item isn't incapacitated.

Actions

Force-Empowered Slam.

Melee Weapon Attack: to hit, reach 5 ft., one target you can see. Hit: 1d10 + Proficiency Bonus force damage.

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Dancing Item

Source: Tasha's Cauldron of Everything, p. 29 - Licenses and attribution