Well, I'm looking at the Awaken spell, and in brief, I'm seeing that it is changing some stats of the recipient of the spell (a creature's Int, for example) or granting stats that the recipient didn't already have (all of the mental stats for a plant).
There is another set of spells that allow for effectively the same thing: The Animate line. Lets look at Animate Object. It says to use the stats as presented by the MM. Fine and good. I take this to mean that I have granted it these stats. Well, one of those stats, and the only one that has a "variable, numeric effect", is the object's HD. So, if I'm using the stats the MM gives me, then a table that had no HD before is granted 4d10+30 by the Animate spell, for the duration of it's effect. Well, that's a "varible, numeric effect", so let's Empower it. Now it 6d10 + 30. Bah, let's Maximize it as well. Why not? Sure, I'd need a Metamagic Rod, but no biggie.
I'm not saying that I think this is or isn't allowed by the rules, and I'm sure someone will argue semantics with me, but it seems that if not outside the letter of the law, then it's at least outside of it's spirit. IMHO, a DM who wants to use an isolated Empowered Maximized Awaken to create a mastermind chipmunk just to mess with his PCs is one thing. But, a high lvl Druid PC dopping a couple thousand XP to fortify his forest with an army of super charismatic paladin tumbleweeds is something else entirely. (Yes, I know they'd have to lvl on their own, but it's a tumbleweed. One kicked my butt IRL the other day, and that was just a normal one I was trying to get out of my yard. I'm sure the super int/wis/cha model would lvl pretty fast.

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