É altamente que criaturas improváveis precisam de descanso para recuperar seus usos de suas habilidades similares a magia; tal restrição seria declarada junto com tais habilidades. Caso contrário,
O jogo não diz ...
Semelhante ao que você deseja saber está nas novas regras do Rules Compendium para itens de uso diário que dizem
Many magic items have a limited number of uses per day. When the last of these uses is used, that power is no longer available for the day, but the item is still magical and might have other powers available. Unless otherwise noted in an item’s description, any item that has daily uses regains all those uses at dawn each day. (86)
Ausente outras regras, isso parece uma boa regra de casa como qualquer outra para gerenciar quando uma criatura recupera seus usos de suas habilidades por dia.
... Mas o Sábio Opinado
Na coluna Dragon # 338 Sage Advice "Respostas oficiais às suas perguntas", o sábio Andy Collins foi perguntado
What exactly does "once per day" mean? Does it mean "once per 24-hour period" or is it recharged after the character rests for 8 hours, like spells?
Para o qual a Collins respondeu
It means that in any given day, the ability may be used once. So what constitutes a day? That's where things get a little tricky and rely on the DM's common senses.
The Sage advises using daybreak as the start of a "day," meaning that all daily-use abilities are recharged in full each morning, regardless of exactly when they were used during the previous 24-hour period. For the vast majority of games, that's when most abilities are recharged anyway (spells, for example), which makes it easy to use.
If your players try to abuse this flexibility--such as by adventuring through the night and then suddenly getting all their abilities back when the sun comes up--the DM should feel free to be more restrictive. It's entirely reasonable to require a full 8 hours of rest before allowing daily-use abilities to recharge (even for those characters who don't require sleep). (84)
Isso é provavelmente o mais "oficial" possível.