@JeremyECrawford can you use warcaster to cast Eldritch Bolt as a AoO even if you're level 5 or higher?
— Harvey Williams (@HarvDWilliams) September 14, 2017
The 3rd benefit of War Caster requires you to target only the moving creature. Eldritch blast works as long as all the beams target it. #DnD https://t.co/WWjgiHQgtD
— Jeremy Crawford (@JeremyECrawford) September 14, 2017
Is this the only example in 5e of using a ranged attack to make an AoO?
Effectively, a Held Action would allow such, too. Warcaster, by its intrinsic nature, allows such by dint of the context of the feat and that the vast majority of attack/targeting spells are, by nature, ranged attacks (even if, as with Magic Missile, there is no spell attack roll involved). Fighers, for example, could utilize this on occasion when coupled with Action Surge (to make “x” attacks during their turn) then use their Action to Hold Action (Reaction) if/when a believed-to-about-to-occur OA is going to happen, then use (if/when appropriate from their earlier turn) a Ranged Weapon attack as their Reaction. (Other feats may allow “x”, as well, as things get published, no doubt.)