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what is the most common numbers people use for army lists in various sizes.
I'm converting the warriors up now and can make 25 + 5 metal.
Personally think it's too much compared to having 60 warriors I currently have.
Army » « Necrons » « Tyranids
The most I have ever used, except for in an apocalypse game, was 20.
10x Marching with the phalanx
10x jumping around with the flying circus
Yes, I did deep-strike your sister...
Necrons : W-8 D-3 L-7 (Sleeping in their TombFoam, waiting for a new codex)
Chaos Forces (CSM/CD): W-42 D-19 L-28
Apocalypse Games : W-4 D-0 L-1 (4 Titans, Brass Scorp, 3 Baneblades, 2 Bombers, 3 Fighters, and a Partrage in a Pear Tree)
Not to give you a non-answer, but it really depends on your army list composition and what you're trying to achieve. You could take 30 immortals, and you could make them work, but you would have to try hard to make it work, and it wouldn't be the strongest or most versatile list ever created. That being said, I believe people typically take 10 immortals per army, if they take Immortals at all. This is because of the Flying Circus tactic, and the maximum allowance of one Veil of Darkness per army only lets us field one flying circus (plus two 10 man Immortal squads and two Lords with Veil and Res orb would be almost be the majority of your army!).
My gaming group's new motto: That army you're using is overpowered because it hurts my guys, codex is broken and needs a rewrite.