I'm reading that Vagrant Story's battle system was divisive on release and many people had trouble hooking onto it. Which is odd, because while I find it complex and cognitively challenging — and probably dreadfully boring to watch — I was pretty much instantly hooked. It really feels like it's building on itself as you finish boss fights and accrue support magic to help respond to situations. The weapon crafting feels like it's rewarding me a lot for being conscious of the battle mechanics.
Retrospectives seem to compare it a lot to Dark Souls and honestly it makes a lot of sense. There's a whole lot of underlying nuance to the battle rules in both that richly reward players who take the time to learn and experiment around them. Playing smart turns a slog into a breeze.
I wish more modern AAA games were as ambitious about defying conventions as this game is. This is easily the most refreshing and captivating RPG I've played in years.