What do the Unown Stones do in Pokemon Mystery Dungeon - Explorers of Darkness?

Answer 1

Each level of Aegis Cave needs a certain set of unown stones to be in your treasure bag. For example, the Ice level needs ICE, then ROCK, and finally STEEL. All other stones are technically useless, but explode against enemies when thrown, doing 60 damage without reduction.

Answer 2

In Pokemon Mystery Dungeon - Explorers of Darkness, Unown Stones are used to unlock the hidden power of the Unown. When an Unown Stone is activated in a dungeon, it can summon a group of Unown that will provide various effects, such as increasing stats or granting special abilities to the player's team.