I'd be tempted to take High Magic on the AM to boost the PG & characters to a 3++. I feel World Dragon is overkill here, Razor makes better sense IMHO. You have points for Obsidian Trinket on the BSB to give a 2++ vs magic. I'm not sure how effective the Helms and DP's will be without characters to help them out. Most lists like this tend to go with Spears or possibly a bigger block of Archers that can contribute ranks if needs be. A couple of mobile redirectors wouldn't go amiss.
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A New Blog (Orcs and Goblins)
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