Unarmed strings in Brawlhalla refer to a series of connected attacks performed without using any weapons. Here are a few popular unarmed string combos you can try:

Down Light (DLight) > Side Light (SLight) > Side Air (SAir):

Start with a Down Light attack (Down + Light Attack) to initiate the string.
Quickly follow up with a Side Light attack (Side + Light Attack).
Finally, perform a Side Air attack (Jump + Side + Light Attack) to continue the combo.
Side Light (SLight) > Down Light (DLight) > Recovery (Jump + Up + Light Attack):

Begin with a Side Light attack (Side + Light Attack).
Immediately perform a Down Light attack (Down + Light Attack).
Finish the string with a Recovery move (Jump + Up + Light Attack) to knock the opponent upwards.
Down Light (DLight) > Recovery (Jump + Up + Light Attack):

Start by using a Down Light attack (Down + Light Attack).
Quickly follow up with a Recovery move (Jump + Up + Light Attack).
Remember that Brawlhalla's gameplay is dynamic and fast-paced, and your ability to string attacks together effectively will improve with practice. These are just a few examples of unarmed strings, and you can experiment and create your own combos by chaining different attacks together.