If I were to run a campaign that might actually go to double-digits, and someone actually stuck it out with a fighter through 9th level, I'd seriously consider house-ruling indomitable to be more meaningful and to convey something closer to actual indomitability. Perhaps restricting the re-roll to STR, WIS, & CHA saves, but also granting proficiency on WIS/CHA saves.
One possibility: Indomitable doesn't get used up unless you actually succeed on your save. So if you're trying to break out of a Hold Person, you can keep applying Indomitable every round until it works, unless your regular save suffices. That will basically halve the duration of whatever effect you're trying to break free of.
I like that as a house rule. Personally, I think the fighter chassis is strong enough without it, but on that same note I was a bit surprised the ability had been cut back that much from the version run in the play test. It certainly wouldn't break the game and I think your idea is much more appealing with such a small tweak.
I was re-reading the PHB last night and realised that while the Fighter's abilities usually refresh after a short rest, the Indomitable feature keys off a long rest. The only other ability that refreshes after a long rest is the Eldritch Knight's spells per day. Has that been corrected in the errata? How would it change the class to have it work off a short rest?
If you're playing in a game that uses the Feats optional rule, and you are specifically including the Resilient feat. Otherwise, the Fighter can just spend those ability boosts directly into Wisdom, after maxing out both Strength (or Dex) and Con.You know what else Fighters get? 2 more ASIs/feats than everyone else. You know what Fighters are not? A MAD class.
With that in mind, you know what feat would help with making Indomitable actually worth using with WIS saves? Resilient (WIS). You should take that feat by Lv. 8 or thereabouts.
You know what else Fighters get? 2 more ASIs/feats than everyone else. You know what Fighters are not? A MAD class.
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