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I don't know if I'm the only one or not, but I love the Ogryns... not so much the way they play, but just the models and small bit of fluff they have.
I was thinking the other day of an excuse to get more of them, and remembered that in the Catachan codex they count as a troop choice. Now, unfortunately, you're limited to 0-1, but that got me wondering...
What would an all-Ogryn army look like? Obviously it wouldn't be "legal" but it would be fun to play with against a friend.... I
Normal Ogryn squads for troop choices, but you would need an upgraded Bone 'ead to serve as the HQ, and it would probably be fitting to give him 1-3 Ogryns as bodyguards, which could be upgraded to Bone'eads themselves. They might even be allowed to take a commissar subject to the normal advisors rule. This would allow them to use chimeras and whatnot.
I'm not sure what you would take for Elites and Heavies, though... droptrooping/deepstriking Ogryns similar to stormtroopers? What about Fast Attack?
I really appreciate the way that Ogryn contrast on the battlefield with the rest of an Imperial Guard army. What I don't appreciate, is that their stats really aren't worth the amount of points that they cost.
At 25 points a model, they incredibly ineffective when compared to other "Assault" units such as Grey Knights, which incidently cost the same amount of points and can be added as allies.
I personally own a full squad of them, but I haven't used them since the "Rhino" rush tactic was removed from the game. When they could assault out of a Chimera, they were still a viable choice, but since they are now forced to foot slog to the enemy, they are nearly useless.
Their only possible role currently, is as a countercharging unit, yet Rough Riders fill the countercharging role much more sufficiently.