[shatner]

Stat-wise, there isn't all that much of a difference between the two. The gold shield is nice, as is the lightning, but neither amounts to a 50 design point difference. Now, the Titan does start with A2E1 whereas the Lord of Storms gets A2W1. That Air-Earth combo makes getting an earth blessing as well as forging elemental staves much cheaper, especially when comparing pretenders with heavy initial path costs.

This next bit is speculation on my part, so keep that in mind. The other reason, the meta-reason, why the Lord of Storms is so cheap is because he's meant to help out water nations, whose choice of gods are much more restricted than land nations. A large part of the latest version of CBM was bolstering underwater nations and it was in that version that the lord of storms was introduced.