Energy Drain

Sometimes characters are exposed to energy drain from undead or evil magic. Such energy drain is manifested in the form of "negative levels." For each negative level a victim receives, they suffer a semi-permanent loss of one hit die worth of hit points, a penalty of -1 on all attack and saving throw rolls (and any other roll made on 1d20), and -5% to any percentile roll such as thief abilities. In addition, an affected spell caster loses access to one of their highest-level spell slots. The victim may or may not be allowed a saving throw to resist the effect (depending on the specific monster type). If the character's hit points are reduced to zero or less by means of energy drain, the victim is immediately slain. If the energy drain is caused by an undead monster, the victim will usually be transformed into that sort of undead (exact details vary by type of monster). Negative levels may be removed by magic, such as the restoration spell. When a negative level is to be removed, divide the total number of hit points lost by the number of negative levels (rounding normally) to determine how many hit points are restored. For example, a character suffers three negative levels of energy drain. The hit point losses rolled were 6, 5, and 2, for a total of 13 points lost. The first negative level removed restores 13 / 3 = 4.3333 hit points (which is rounded to 4 even). Now the character has two negative levels and has lost 9 hit points. The next time a negative level is removed, the character recovers 9 / 2 = 4.5 hit points, which is rounded to 5 even. Now the character has one negative level and 4 hit points lost. Removal of the last negative level will restore the remaining 4 points. Those who have suffered energy drain generally have a gaunt, haggard look about them, noticeable by observant characters.