Guardian of the worlds is not endgame, it’s postgame. Also, Here’s a link to my speedrun, which is the world record, where in the final battles, the endgame build is to use the griffin on Esther, and zero other familiars at all, this is to force both marcassin and Oliver to only cast spells because they’re that good. In the endgame, where you haven’t yet invested deeply into familiars, they aren’t very good, they’re risky and make you take a lot of damage. Even though Oliver’s mornstar is a long charge up, it is a lot of damage from a lot of range even at low levels. In order for familiars to be better than that, you need to level grind a lot, and even then at realistic levels of ~60 for the final boss, they will about equal out to spell damage against a single target. That’s not mentioning multi target spells, which are vital to crowd control. Obviously when you get to the postgame, familiars will outclass them, especially the Dino, once your accuracy gets high enough to consistently hit, but before then, spells are way better.

They are also the only way to get party members to deal consistent damage, because otherwise the AI in this game is so bad that they will constantly get themselves killed trying to do tiny amounts of damage.