In the 99, Daxos the Returned seems like he could be a good ally for Enchantment-abuser heavy-weight Zur the Enchanter. In fact, it's a question I see asked quite a bit. Can they really join forces and benefit one another?
On paper, it does seem like Daxos the Returned could find a little niche to carve out in this deck. Even if Daxos only nets you a small handful of experience counters while he's on the board, creating a bunch of 3 mana Enchantment creature tokens can't hurt. But the issue is that Daxos's ability makes him far better as a Commander, as once he's removed from the board, Zur doesn't really have an easy way to get him back. So while there is some loose synergy as far as how many Enchantments you would end up casting in a Zur deck, the token plan doesn't really mesh with what Zur is trying to do. That is, lock other players out of the game with a bevy of cheap but effective Enchantments and slowly but surely whittle away your opponents with a protected Zur himself.
Are there other Commanders that could use him effectively as an Ally within the 99? Teysa, Orzhov Scion seems like a good fit, as she's often looking for white creatures to sacrifice in order to exile opposing creatures. Also, because the tokens re both white and black, these tokens benefit from her second ability, as well. In sacrificing those tokens, they become replaced with 1/1 white Spirit tokens with flying. So there is some loose synergy there.. But it's unlikely that you'll amass many experience counters as Teysa only runs a modest amount of Enchantments in her decks.
Daxos's mate from Commander 2015, Karlov of the Ghost Council, does like a bunch of Enchantments in his decks, although the synergy outside of the pure amount of Enchantments you'd be casting isn't obvious. There aren't any other decks in either White/Black or White/Black/Blue that are obvious homes, either.
In White/Black/Green (Abzan), however, there are the popular token-happy Commanders Daghatar the Adamant and Ghave, Guru of Spores. Both decks play a fair amount of Enchantments, and Daxos the Returned could prove to be a useful token generator. Still, it's sort of an awkward combination.
Like a good many Legendary Creatures created specifically for the Commander format through the pre-constructed decks, Daxos the Returned is best utilized when built around as a commander.