well thats roughly around 200 dollars worth not 300 as i have bought a 300 dollar grey knight force for christmas.
mostly i would say use the grey knights as the fast attacks so that they truely can shine. and never use purgatation squads. your paying way too much for something that is only a little better than a heavy bolter
may i suggest using 3 squads of grey knights as fast attacks and enough squads of storm troopers to full fill any anti infantry fire support. also 2 dreads
ill continue later
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