@Dr_Blamo has requested that spells avoid targeting a player's own Sentinels.

Unfortunately this is not exposed by Citizens itself, which I think means I would need to dig into an NPC for the Sentinel trait, which also means adding another dependency on Sentinel itself.

I'm not really sure I'm going to do any of that at this point, so I will close this issue one way or the other, if I decide for sure it's not something I'm going to explore.