They help ensure that the forges of the dwarves are always squeaky clean
It also fights against the politics of EDH by giving every player a definite enemy for them to focus on
Reyhans just fine in a vacuum, but 2-color partners are always way more powerful than they seem
Note that storm-style cards, which are often used in chain combos, are too obstructive in the opening hand, and since there is no search, the probability of them coming to hand when you want them is low, so I have not included them this time
Kess, Dissident Mage is also a great commander if you want to build a spellslinger deck
Before that copied untap resolves (and whiffs, because Basalt Monolith is already untapped right now), tap Basalt Monolith to make three more colourless mana