Quicksand took the stage for the first time since disbanding in 1999 on Sunday at the Revelation Records 25th Anniversary Shows in Pomona, California.

The highly rumored surprise set saw the band performing songs from 1993's Slip and 1995's Manic Compression. Video footage is below.

While Sunday's performance at The Glass House appears to be a one-time reunion, it is rumored that the band may play a show in New York City later this year.

Since breaking up the members of Quicksand have stayed active with other projects. Notably, frontman Walter Schreifels plays in Rival Schools and longtime band Gorilla Biscuits, while bassist Sergio Vega performs in Deftones.

The lineup has been announced for "This Is Hardcore Fest 2012," taking place in Philadelphia, Pennsylvania on August 9th through 12th. Details follow:

August 9th @ Union Transfer

Terror
Earth Crisis
Ringworm
Maximum Penalty
Mindset
Naysayer
Lifeless
Build & Destroy
The Storm

August 10th @ Electric Factory

Headliner TBA
Cro Mags
100 Demons
Death Threat
Harms Way
Power Trip
Praise
Wrong Answer
Beware

August 11th @ Electric Factory

Gorilla Biscuits
Lifetime
H2O
Title Fight
Bane
Greyarea
Vision
Horror Show
Rival Mob
Rotting Out
Skin Like Iron
Stick Together
No Tolerance
Twitching Tongues
Code Orange Kids
Oblivion
Empire of Rats

August 12th @ Electric Factory

Blacklisted
Breakdown
In My Eyes
Floorpunch
Crown of Thornz
Negative Approach
Killing Time
Wisdom in Chains
Nails
Hard Skin
Gehenna
Soul Search
Will to Live
Agitator
Rude Awakening
Born Annoying