This spell may be cast on any
one Hero, including yourself.
The next time that Hero attacks,
he may roll two extra combat dice.
The spell is broken the moment the
Hero can no longer "see" a monster.
I gotta go with drathe and AerynB and say the spell only works on the next attack, then is done. This puts it more in line with the power of the other spells. Otherwise, a broadsword + Courage = multiple Genie spells. On p.1 of this post, AerynB already sufficiently demonstrated legitimate situations that explain why the last sentence of the spell is included for a one-off attack interpretation (quote added as an edit):
AerynB wrote:drathe wrote:The only other reason I can think of is the chance that the spell is defunct should the Monsters escape sight before the attack.
Hmm...I think I see now. All the Heroes have attacked already, and maybe Elf/Wizard casts the spell on somebody standing next to a monster for the next set of turns. Zargon knows this, lets his monster attack, and then moves away so the Courage-ous Hero doesn't see any more monsters...voila, the spell is broken before the Hero had a chance to attack with the enhanced use of the spell. Or maybe Zargon only moves some of the monsters away, but the other Heroes attack and kill all the visible monsters before it's the Courage-ous Hero's turn so the spell wears off before he gets to benefit from its effects.
Good news for a beleagered Zargon and game balance.
Kudos to Ethica. Never occured to me that a Hero could more efficiently cast the Courage spell before encountering monsters; no longer "see" doesn't take effect until a Hero first "sees". However, for reasons I cited above, I don't agree the bonus dice carry over to more combat turns.