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You have found a potion from the Tavernmaster's private collection! Feel free to use it in your role-playing sessions. If you are a player, assign it to ONE of your characters. If you are a Game Master, be sure to remove the label before placing the bottle in your dungeon...

Small Beer (1 dose)

Knocking back this little bottled beer shrinks you to one-tenth your normal height, including your clothing and equipment, for a period of 10 minutes. Your combat scoring remains the same, although of course your speed of foot-travel is reduced to one-tenth normal.

If you fail an SR on LK at your own level, your clothing and armour does not return to its normal size. (You may wish to loosen the fastenings on your hauberk...)