Ki Ryn said:
Can they be? Yes.
Should they be? No.
Shield and Truestrike potions, at least, are rather unbalanced.
What's so unbalanced about Shield potions?
Remember, for potions, wands, and so on -- the "caster level" is presumed to be the *minimum* needed to cast the spell. So a 50gp-ish potion gives you the Shield bonus as thought from a 1st level caster ... so, for one minute: ten rounds. It will take your action for one round (presuming a potion belt or similar), to gain that benefit at all.
Now, me, I want to know why Brew Potion doesn't already let you opt for Oils / Salves. It's the required feat for such nifty items as Oil of Slipperiness. 8)
IMC, I allow most single-target spells to be rendered into potion, salve/oil, or similar forms (such as a powder to mix into a drink; takes more time, but it's more portable ... good for those "between encounters" use potions).
External-effect spells pretty much
need to be in salve or oil form -- i.e. Shield spells. Apply externally, gain benefits thereof.
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Oh, and Ice BEar -- Mithril Shirt. Mage Armor. Etc.
Not to mention the gp/xp cost for ten rounds of protection.
And on top of it all, since Shield provides a Cover bonus, it's susceptible to Sharpshooter, or at Epic levels, Uncanny Accuracy.
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