You've stated that Anders used gaatlok to destroy the chantry, but isn't gaatlok just gunpowder? Gunpowder doesn't cause beams of red light and hovering debris, so magic pretty much has to be a major component of Anders' bomb doesn't it?
I think it’s at least possible that magic was used to light the fuse. I mean, there are two possibilities here: either Anders lit if from all the way down in Lowtown, or everything he was doing down there was just a signal (and a spot of misdirection) so his allies could light it from up close.
The advantage to the idea of him having allies is that it simplifies things enormously. If you look at the illustration in World of Thedas II, the barrels are all hanging from the ceiling of what is presumably the Chantry cellar. Hawke doesn’t distract Elthina for very long, and the whole thing looks more plausible if it wasn’t just one guy running around setting things up. It also makes the explosion itself much more explicable. It’s quite a long way from where Anders was standing to the Chantry, and casting a spell from there seems improbable. Not impossible, certainly: one thing that’s clear is that it’s Justice acting in that scene as much as Anders, and it’s hard to be clear on Justice’s limitations – but improbable.
Levitating the debris, too, which isn’t a part of the bomb but a means of containing the damage, looks far more doable if you imagine a number of people involved. Otherwise, that was … well, the word ‘miraculous’ seems applicable.
The disadvantage, of course, is that there’s no direct evidence of Anders having such allies. We know rebel mages were present in Kirkwall that year – the Resolutionists – but we don’t have any indication they were in contact.
The trouble is, if he didn’t have help, then … what the hell? Magic isn’t really something you put anywhere. It’s something you do. I realise that line gets a little blurry with glyphs – but I don’t think modern magic, at least, has glyphs of that power, and him running around casting (and somehow maintaining for weeks or months) a lot of glyphs seems even less likely than hanging up all those barrels. Now, runes – enchantments – those you do put places. But Anders is a mage. He couldn’t make those himself. So we’re back to him having help again.
If it was just Anders, doing magic, then … we’re looking at a truly extraordinary amount of power. Far more power than than we’re given any reason to think either Anders or Justice possesses. If Anders is that tough, why do I have to carry around an emergency stash of Mythal’s Favour bombs for when my healer gets knocked out? :)
I’m inclined to think he had help.
As for the weird light in the Chantry – I don’t actually think that was anything Anders did at all. Now, the endgame is light on facts, so I want to be clear: I’m talking about what I think works thematically, not anything I can prove happened with dialogue and Codex entries.
One thing Dragon Age 2 does very well, I think, is give you a strong sense of stories beyond what you’re seeing. There are so many things people say, or hints that we get, that are never expanded upon. Hawke will poke their nose into a lot of things, but I suspect even the most diligent, Codex-entry hunting Hawke possible still barely scratches the surface of Kirkwall’s issues.
But one thing that we do know is nothing in Kirkwall is being used for its original purpose. This is an ancient Tevinter city. The Viscount’s Keep and the Chantry were once the homes of Magisters – and since these are the most impressive buildings in the city, I think it’s reasonable to assume these were the homes of the governor and the city’s high priest. We know from the work of the Band of Three that the layout of Kirkwall was deliberate. The streets are in the shapes of glyphs, and apparently the blood of thousands of slaves was deliberately shed to thin the Veil. The whole city is quite literally a magical machine.
And … a lot of bad things happen in the Chantry. A lot of bad things happen everywhere in Kirkwall, obviously, but some spots are worse than others. You might expect knife fights every Tuesday in some Coterie-controlled slum, but the Chantry is in one of the wealthiest parts of Kirkwall, where there are frequent guard patrols and the Chantry’s private army of Templars should serve as night watchmen.
And yet it is consistently the site of murders, betrayals and ambushes. The Chantry – the building itself – is bad.
Kirkwall is intended to be a microcosm. All the same abuses are happening elsewhere, but usually behind closed doors. In Kirkwall, evil oozes out between the cracks of civilised society – so you see every terrible thing that happens to every oppressed group up close and on a daily basis. And that’s because of the magical machine built into Kirkwall’s very streets.
So – sure, I think the apocalyptic look of the Chantry explosion is magic. But not Anders’s magic or Anders’s bomb. It’s the magic of Emerius, that’s always been there, and that the Chantry has long been arrogant enough to ignore. It was in the damn walls, and it chewed happily on all their dirty little secrets and then spat them out onto the city streets for the whole world to see, and when it died it did so with panache.
And given the Deep Roads expedition, the nearness of Corypheus, the deliberate thinning of the Veil, and the Forgotten Ones – I think that red was also a hint of red lyrium.