Pyramid
Pyramid is an Adventure Map location, which is guarded by a stack of 40 gold golems and two stack of 10 diamond golems. After defeating the guards, he will learn typically a fifth level spell provided that he has Expert Wisdom and a spell book – if he does not, the spell is lost forever. However, pyramid can also give hero Frenzy spell, which is a fourth level spell.
If the hero retreats or dies during the battle, the already defeated golems are replenished (unlike in creature banks). Searching an empty pyramid decreases hero's luck by -2.
A curious detail is, that in the version 1.2 of Restoration of Erathia, a hero could recieve a message that he has learned Fear spell from the pyramid. However, no such spell was added to the spell book. This anomaly was removed in the version 1.3.