|Crude diagrams on this altar and its twin invite you to place items upon them.|
Commutation altars can swap the enchantment levels of two items, but only once.
Found on depths 13-26, these altars can be extremely useful if you have found a new item you would prefer to have enchanted rather than an old one.
Once you place two valid items on the altars, their enchantment levels will be swapped. Runics are not affected. The strength requirement for weapons and armors will not be affected either. Nothing will happen if the two items have the same enchantment level.
Giving a staff an enchantment level below +2 will destroy the staff. Giving a charm an enchantment level below +1 will destroy the charm.
In Brogue 1.7.4 not only the altars, but the whole chamber is working as commutation machine. So take care not to you drop useless, cursed or empty items on the floor inside the commutation chamber and then proceed to place your valuable items on the altar. This might destroy what you want to commute.