Sleep

To sleep, use a sleeping bag or bed when the 'sleepy' or 'needs sleep' status effect is displayed at the lower left corner of the screen. You can also sleep by resting when you need sleep.

While sleeping, you can gain bonuses based on your experience level. These bonuses can come in the form of attributes, skills, spells, and more. Take care to sleep in some form of bedding, however, as sleeping without it will result in gaining only half the usual benefits. Superior beds (like the king's bed in Palmia) generally provide greater bonuses during sleep.

Traveling on the world map will cause your character will take the occasional nap, which alleviates the need to sleep but does not allow you to dream.

Avoiding sleep for long periods of time will cause you to temporarily lose speed and all your stamina, rendering you unable to use abilities or skills.

Dreams

While sleeping, you may also have some dreams which may cause certain events to occur. Whether you get good or bad dreams appears to be correlated to your Luck.

Good dreams

• Receive spell stocks for a random spell; note that you may actually LOSE the spell altogether if you have too much (Title:Strange Dream)
• Gain random materials
• Have your Meditation skill improved
• Have your Healing skill improved
• Have your Faith skill improved (only if you aren't worshipping Eyth of Infidel)
• Gain potential in a random skill
• Get the Lucky Day (+777 Luck) buff for 1500 turns (Title:Mewmewmew!)
• Receive a treasure map
• Have the potential of one of your attributes increase
• Receive the Statue of Ehekatl

Bad dreams

• Lose resistance to darkness or have a curse placed on your equipments (Cursed Whisperings; those with the Exorcist feat will get a message saying that 'Your prayer negates the curse.")
• Randomly mutate; may be either a good or bad mutation, however (Title:Monster dream)
• Lose money to thieves (can happen in your own house)
• Creepy dream, lose resistance or a mutation, the worst one. Unknown if cursing word protection also protects against this, possibly just lowers probability. Will only decrease intrinsic resistances gained by eating corpses and thus, won't take your racial/bonus resistances or drop any resistance below zero. Will do nothing if you haven't gained any resistances yet. (Title:Keh lah lah)