Having two Clarion Spirits makes it so that a game can typically begin along the lines of foretelling Doomskar Oracle or Iron Verdict on turn 2, turn 3 cast Clarion Spirit, and then cast the foretold card
While that may be the case some of the time, a lot of the rest of the time, games will end shortly after a wrath as the board is unlocked
Fetch Lands Pay 1 life, sacrifice the land, and go grab the exact land type you need
You could also go for a more midrange option
It won't turn any land into a basic land or remove the legendary supertype from a legendary land, and the lands won't be named "Island." If Harbinger of the Seas loses its abilities, it continues to turn nonbasic lands into Islands
The only downside is that you dont get colored mana, so you are restricted on the spells you are able to cast