It's sad because there is absolutely no way to do this in 3e. If I send 30+ enemies at the PC's, even if I go a 5+APL on the EL, the mooks are going to be so low on the CR scale that they are not any challenge.
And, wasting time at the table while the players roll endless d20's with absolutely no threat of failure is not my idea of fun.
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Umm, no you couldn't. How do you make a creature with 2 hit dice only have 1 hp? And, while you complain about the unrealism of minions, you have no problems with hundreds of people having only 1 hp?
Let's see you create a 10 hit dice creature, with 1 hp, and a +15 attack bonus in previous editions. I'll wait.
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The mechanical solution you provided doesn't work either. You gave it 10 hit dice, but no feats, no skills and no CR. And, you cannot simply decide, in 3e, that a creature has less than 1 hp/hit die, unless you drop it's Con below 10. Which doesn't really work on a 10 hit die creature anyway.