See if you can get your DM to okay these custom magic items, since wizards shouldn't be the only one who gets nice stuff.
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Tankard of Overflowing Drink
If a Tankard of Overflowing Drink is submerged in a draught of an alcoholic beverage it absorbs that spirits of that beverage into its being. Until the tankard is submerged into a different alcoholic beverage it will constantly reproduce the type of alcohol it was last filled with. It only does this when the tankard is brought to the lips of the wielder, the tankard will appear empty when it is not hold by the user, nor can the tankard contents be poured into another container.
In addition when one drinks from the Tankard of Overflowing Drink he may choose to imbue himself with unbridled strength unleashed via the fermented liquor during this time his unarmed strikes are treated as being 2 sizes larger than they normally are, this benefit lasts 8 hours. The Tankard of Overflowing Drink may be used in this fashion 3 times per day.
Finally when yielding a Tankard of Overflowing Drink as an improvised weapon, treat the Tankard of Overflowing Drink as a magic weapon for the purpose of overcoming damage reduction. The damage done by the Tankard of Overflowing Drink is equal to 1d4 (x2 on a critical hit) or your Unarmed Strike damage whichever is higher. If you have drank from the Tankard of Overflowing Drink in the last minute, you do not take the traditional -4 attack penalty due to nonprofiency when using the Tankard of Overflowing Drink as an improvised weapon.
Moderate Transmutation; CL 8th; Craft Wondrous Item, Greater Mighty Wallop; Price 25,920 gp; Weight 1/2 lb.
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Greater Tankard of Overflowing Drink
As Tankard of Overflowing Drink but increase your unarmed strike damage by 3 sizes instead of 2.
Strong Transmutation; CL 12th; Craft Wondrous Item, Greater Mighty Wallop; Price 38,800 gp; Weight 1/2 lb.
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Ultimate Tankard of Overflowing Drink
As Tankard of Overflowing Drink but increase your unarmed strike damage by 3 sizes instead of 2.
Strong Transmutation; CL 16th; Craft Wondrous Item, Greater Mighty Wallop; Price 51,840 gp; Weight 1/2 lb.
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These custom magic items are based on the spell Greater Mighty Wallop from Races of the Dragon. They follow the crafting guidelines of Command Word magic items.
Spell Level*Caster Level*Command Word*Three Times Per Day
25,920=3*8*1800*3/5 2 Size Increases
38,800=3*12*1800*3/5 3 Size Increases
51,840=3*16*1800*3/5 4 Size Increases