It's about five minutes into Slayer's set when it hits me with high-definition clarity: what's been souring my love for this band over the course of particularly the last five years is their (and I mean Kerry King especially) continued, ill-conceived goading of Christianity. Not that I'd have a problem with someone airing an opinion of course, but when that opinion is coming from a self-professed Roman Catholic -- well, it just comes across as a little weak is all. If you're going to talk about anything, at least try and convince me that you stand firm by what you're saying. In fact, while we're at it, if anyone is going to start talking about the evils of religion, then surely Islam has a hefty comeuppance just itching to be meted out. But let's be honest here: calling for the prophet Mohammed to be sodomized would take gonads the size of monster-truck tires, and the individuals in possession of said testicular fortitude are in very short supply.

Then again, no one ever came to a Slayer show -- or any other metal gig for that matter -- to philosophise. No, what draws the punters is unbridled aggression and energy delivered via the most riotous means possible, and there's certainly plenty of that on offer tonight. For starters, a dismal mixing job renders Children of Bodom's Yngwie Malmsteen-like take of melodic death metal virtually impotent. They still give it their all though -- ripping into their every song with gusto and overcoming the gremlins in the soundboard with commendable flair.

By contrast, Lamb of God have a crisp production on their side and all the bullish attitude necessary to make a five thousand strong-audience at the Brixton Academy forget who tonight's headliners are. Laying it on thick and fast early on, "Ruin" and "Laid to Rest" are colossal riff-monsters -- punishing and inventive. Newer material such as "Walk With Me in Hell", "Pathetic" and "Redneck" hit even harder, and it's clear that more than ever Lamb of God are the shoo-ins to be Pantera's successors as the undisputed heavyweight champions of gritty, beer-swilling, seditious heavy metal. Add to that a song as multi-dimensional and mesmerising as "Blacken the Cursed Sun" and you have legends in the making.

The last time I encountered In Flames in a live setting, I left after two songs. Tonight, I'm less inclined to retch at the sound of their ultra-slick melo-death, admiring instead how they've grown as a band. Clearly the most comfortable of tonight's acts in a large venue, they're energetic, engaging and strangely seem quite humbled by the generous response they're afforded by the London crowd. Fleshing out their set list with vintage numbers from _The Jester Race_, they hit all the right buttons; and while I still find their music cumbersome at the best of times, there's little denying that they have evolved into a live force to be reckoned with.

Of course few acts define that as vividly as Slayer. Over two decades of aggression (pun intended) they have laid to waste many a stage, and left a myriad of goggle-eyed fans in their wake. Annoyingly they start off rather tepidly, electing to air "Disciple" as their first song. It only gets better from there though, with the rapid fire onslaught of "War Ensemble" tearing through the crowd like a hurricane through tumbleweed. "Spirit in Black" provides a welcome surprise, and even "Jihad" -- a tawdry affair from their latest opus -- works well in a live setting. Continuing with the likes of "Post Mortem", "Seasons in the Abyss" and the obligatory "Raining Blood", the set tangs of being formulaic, but it hardly matters in the light of such a class performance. Yes, Slayer aren't quite the trailblazers they used to be, and yes, their psuedo-Satanism would be better suited to a troupe of five-year olds. For all their flaws though, they remain a live institution that's rarely bettered.