Mine

delete from items using items, armor, characters
where items.item_id = armor.item_id AND armor.crystal_type = 's'  AND items.owner_id = characters.obj_Id AND characters.accesslevel < 100;

delete from items using items, armor, characters
where items.item_id = armor.item_id AND armor.crystal_type = 'a'  AND items.owner_id = characters.obj_Id AND characters.accesslevel < 100;

delete from items using items, weapon, characters
where items.item_id = weapon.item_id AND weapon.crystal_type = 's'  AND items.owner_id = characters.obj_Id AND characters.accesslevel < 100;

delete from items using items, weapon, characters
where items.item_id = weapon.item_id AND weapon.crystal_type = 'a'  AND items.owner_id = characters.obj_Id AND characters.accesslevel < 100;

delete from items using items, etcitem, characters
where items.item_id = etcitem.item_id AND etcitem.crystal_type = 's'  AND items.owner_id = characters.obj_Id AND characters.accesslevel < 100;

delete from items using items, etcitem, characters
where items.item_id = etcitem.item_id AND etcitem.crystal_type = 'a'  AND items.owner_id = characters.obj_Id AND characters.accesslevel < 100;