When the audience start spilling onto the stage and the bouncers cannot tell drunken admirers from drunken band members, well, that’s when you know you’re at the right gig. It’s no Stooges-like stage invasion – thrashing and fighting for space – but it’s entertaining enough. And if there’s one thing Foxygen, the “21^st Century Ambassadors of Peace & Magic” know how to do, it’s put on a chaotic and spasmodic spectacle of a show.

Support comes from Cardiff-born Huw Evans a.k.a H. Hawkline. The psych-pop four-piece power through an eccentric set of songs, hop scotching from vague shoegaze to jagged indie meltdowns. Huw’s phantom guitarist, “Sweet Babs”, who remains partially hidden behind a speaker stack, adds jittery guitar lines to Huw’s wonderfully weird songs ‘Concrete Coloured Clothes’ and ‘Spooky Dog’. Sounding somewhat like a patriotic Parquet Courts, they even pull off enlivening “Welsh traditional” punk.

After taking their leave to drink and catch up on the election results, the stage is cleared, leaving pentagrams, patchwork dolls and guillotined mannequins in full view. Then fairground music begins to play. Written down that sounds fairly horrifying, where in fact it just added to the hilarity and outlandishness of what was about to ensue.

On waltz the band, Shaun Fleming in heavy guy-liner and Rado in a fringed rodeo jacket, with three pretty sequined backup singers in tow. Sam France then stumbles in through the crowd to the lip of the stage and the mood is set. Launching into their convulsing opener, France flaunts and throws himself into the crowd in an expected Iggy Pop meets Jagger manner.

The songs throughout the night seem to loosely resemble the album tracks, in the same way a conversation shared formally at work shifts dramatically when told wild and drunk at 3 in the morning. Loud, hard to follow, completely unrestrained and in that moment, exciting as hell; I’ve seen some reviewers palm-off Foxygen’s live performances/stage presence as bratty and puerile, however this guy – and the onlookers around him – well, we were completely sold on the whole wacked-out circus act.

Some of the sword fighting, hammy back-and-forth between Rado and Sam (“We’ve come a long way since Cali haven’t we Jonathan?” “We sure have Sam”) and bastardised Beatles covers could be perceived by some as annoying, pretentious, whatever fits. But this is a band whose whole musical process is a pisstake; it’s been a sprawling experiment since their school days. Who cares if they haven’t grown up since then, it’s the “anything goes” attitude, which makes it all so disastrously perfect. In fact it’s not posturing; it’s frank, freak-flag-flying honesty. I salute it, whereas it’s totally understandable that others may detest it.

After play fights and questionable stand-up routines (“I hear you’re electing a brand new stuffy white man tonight, you should get yourself a cool black guy”) they return for an encore and clatter through ‘No Destruction’. There’s been talk about this being their last tour, in fact even the last of Foxygen altogether. I’m sure in whatever forms the various members next surface, there will be no stopping the trajectory of their creative calamity and I can assure you, we’ll be waiting down the front.

David Weir