As one of the Gods from the original Theros block, Phenax has amazing sticking power through the combination of having indestructible and the ability to avoid any cards that exile creatures like Path to ExilePath to Exile and Swords to PlowsharesSwords to Plowshares (two of the most common cards in the format in 62 and 41% of possible decks respectively) thanks to the fact that if you don't have a ton of permanents in play to give you devotion to make it a creature
TheChirurgeon: Yeah this one is solid
is certainly the best of the cards found in its four Commander decks
If you have old-school dual lands like Tundra, Plateau, Volcanic Island, Sacred Foundry, Steam Vents, and Hallowed Fountain they would certainly tighten up your mana and make multiple Zedruu activations easier
The same is true if an opponent's permanent gains one of those abilities after Shay Cormac's first ability resolves
An equipment-based commander wants support pieces like Puresteel Paladin and Stoneforge Mystic that dont interact with enchantments