The discussion about maneuver save DCs has made me mull over whether Restless Bones maneuvers even should be Int-based, or if Str-based DCs would be more appropriate. Aside from Bone Puppet (which was missing its save DC formula) and Ossifying Blow, the various maneuvers with saves are more about bone-shattering force than about precision or necromantic weeaboo fightan magic. This is also important because Death Knights get a bit of MAD if they feel a pull for Int for these maneuvers (Str/Con for your standard melee combatant, can't completely dump Dex because of AC even if heavy armor means you don't need more than 12, a bit of Cha for class features and Devoted Spirit DCs, and Wis for Undying Call and Frozen Night DCs, which admittedly are less common and less important). I mean, they aren't dependent on having high everything, and should be able to function quite well even with dumping all 3 mental stats, but they're definitely missing out.
For reference,
ToB discipline save DC types, although most disciplines only actually have a couple of maneuvers with saves, and several of them have DCs set by other factors like attack or damage rolls to boot. ALL of the Warblade disciplines (except maybe White Raven, which has no saves) are Str-based, only the Swordsage exclusives of Shadow Hand and Desert Wind are Wis-based, and the only Cha-based discipline is the Crusader-exclusive Devoted Spirit. ToB looks semi-random with its save DCs, but when you look at it form a distance, it's actually finely crafted to avoid MAD. The only classes that want anything other than Str for the maneuver save DCs are classes that want those other ability scores for class features already.
0) Keep the saves as Int-based. This leaves Restless Bones as the only reason for a Death Knight to want Int. Class features and Devoted Spirit run on Cha, and Frozen Night and Undying Call are Wis-based. I'm just listing this for reference, because I'm definitely not leaving it that way.
1) Switch the saves to Str-based. This reduces MAD a bit, since there are quite a few save-based Restless Bones maneuvers, so actually keeping the DCs up is more important than with other disciplines. However, using Str for supernatural maneuvers like Bone Puppet and Ossifying Blow, where the effect being saved against is entirely magical, not physical, feels odd.
2) Switch the saves to Cha-based. Most of the maneuvers with saves are about brute force, though, especially the ability score damagers (unlike Shadow Hand which is fluffed more about sapping your opponent's vitality), so Str fits most of them way too well.
3) Switch the saves of the non-supernatural maneuvers to Str-based, and change the supernatural maneuvers to be Cha-based. Not as far-fetched as it sounds, as Setting Sun forms a precedent (one Str-based maneuver and one Dex-based maneuver, albeit in a discipline with only two maneuvers with saves and a strong penchant for working with both ability scores in its other maneuvers). Bone Puppet, Ossifying Blow, and possibly Bone Shard and Bone Spear (I'm on the fence on whether their physicality trumps their technically being supernatural abilities) would be Cha-based
Also, regardless of how Restless Bones's save DCs change, I'm swapping Frozen Night to Cha-based save DCs.
Undying Call will remain Wis-based, as it's tied closer to the Spirit Warrior than the Death Night, it doesn't fit at all for Str-based DCs, and it doesn't have much that requires saves anyways so it's not a big issue. I suppose I could change it to be Cha-based and then alter the 1st-level Spirit Warrior class feature to also shift your Cha-based maneuver DCs to Wis-based like it does for skills and incorporeal AC, thus leaving both classes as DAD (dual attribute dependent) for maneuver DCs. Hm, that doesn't actually sound so bad, especially since Spirit Warriors have access to the Cha-based Devoted Spirit already.
I don't know why I'm worrying and arguing about Devoted Spirit, though. It's got all of 2 maneuvers with saves, and one of them has the DC set by your damage done so it doesn't count. Only Castigating Strike has a Cha-based save DC in Devoted Spirit. Eh, consistency.
Edit: Also, changed the Grim Reaper so Dread Necromancers can use it too.