Crown

The Crown of Lord British is an item of immense magic power. Whoever wears it, negates the use of magic by the foes of the wearer, or posession of the wearer and his/her friends. Only very powerful creatures like the Shadowlords can withstand its powers.

The Crown was the first item sized by Lord Blackthorn after corrupted by the Shadowlords. He hid it on top of Castle Blackthorn, behind a magically locked door, guarded by demonic statues. The Avatar however managed to regain the crown, using it on his/her quest to withstand demonic powers in dungeon Doom. After that, the crown stayed with Lord British.

Trivia

 * A little gag in the series is the fact, that in no two Ultimas, the crown looks the same.