Punk foursome Beach Slang set the bar high Saturday night at Neon Reverb, and then fuzz-rocker Ty Segall obliterated it completely on Sunday, capping the weekend with a manic performance ranking among the Downtown festival’s all-time best.

The California songwriter and his crack five-piece band, The Muggers, brought ferocious energy to the Bunkhouse and never let up, turning a huge swath of the packed house into a sea of swirling, smiling faces.

Segall arrived onstage in a creepy baby mask (think: Sloth from The Goonies, but with teeth), signaling a focus on corresponding new album Emotional Mugger. The mask lasted just one song (and reappeared for one more later), but the theme carried through the majority of the set, as the six musicians played Segall’s terrific January LP in order, track by track, minus avant-collage piece “W.U.O.T.W.S.”

Witnessing Segall sans instrument felt strange initially (he typically plays blinding guitar, or bashes a drum kit with psych-rock project Fuzz), but that actually freed him up to connect with the crowd more directly. He spent much of his 55-minute set at the very edge of the stage, singing wickedly into the faces of those below, gesturing forcibly with his hands and, at one point, pushing the Weekly’s assigned photographer into crowd-surfing position atop outstretched arms below.

The band’s massive—and superbly mixed—blend of garage, glam, punk and noise never lacked for Segall’s own riffs, as the quintet behind him sounded less like a pieced-together collective than a road-hard unit. Kyle “King Tuff” Thomas, who brought a sleaze-funk touch to his leads on “Mandy Cream” and “Squealer Two,” and keyboardist Cody Hanson of Wand, who unleashed a mess of nifty effects during the middle stretch of “Emotional Mugger/Leopard Priestess,” stood out, but bassist Mikal Cronin, drummer Evan Burrows (another Wand regular) and second guitarist Emmett Kelly (of The Cairo Gang) were no less responsible for Sunday’s magical mayhem.

A fivesome of Vegas bands sharing the Bunkhouse bill also deserve kudos, for helping set the scene and producing some interesting music along the way. Bluesy trio American Weather got it started early, followed by another three-piece, the promising Special K, whose youthful members’ obvious affinity for Pavement has helped steer their songwriting choices.

A third trio, Headwinds, took the night to a heavier place, producing a series of dense, reverb-soaked rockers, before Dark Black—featuring three ex-members of Caravels—then demonstrated how different its throbbing, post-punk-ish new tunes sound from those of that defunct hardcore band. Lastly, scene anchors Same Sex Mary paired a theatrical visual presentation—complete with a stuffed, corpse-like form that wound up hanging from the rafters—and a well-considered song sequence as it warmed up for some unofficial South by Southwest gigs later in the week.

If one were to quibble, it would be the night’s abrupt ending. After finishing off Emotional Mugger with the hypnotic, Kraut-like number “The Magazine” and plucking three songs from Segall’s catalog, topped off by a vicious version of 2014’s “Feel,” he and his Muggers simply left. Though a sizeable audience remained, and heartily chanted for more, they never came back, an odd footnote for a four-day festival that had truly earned its encore.