Hmm, okay, let me look at them then.
Battlebred is similar to the more basic extended rage feat, and the 2 and 2 is usually effectively the same as a single 3
Chosen of the Deathless has half of Augment Healing and then about half of the turning check benefit of Improved Turning (+2 to the roll is 2/3 of Improved Turning unless you rolled a 22 without needing the +2, in which case it didn't help you) and then twice the turning damage benefit of Improved Turning. All in all, it is above par and aids Clerics, but not by too much and you have to be an Aerenal Elf, so it should be okay.
Manifest Druid is fine because the last ability is unusable unless you foolishly multiclass
For the Manifest Spellshaper, under no circumstances does it work on infusions, right? Because Mastery of the Battleground would apply to a large number of Artificer infusions and thus be a big power boost.
I agree with you Erekose--Mastery of Day and Night is utterly absurd.
Mastery of the Dead is *very* strong if you can actually slay something with a Death Descriptor spell. It makes bringing minions against a high level Necromancer a scary risk.
Mastery of Dreams is just strictly better than Spell Focus (Illusion). Why? And why pick the school of Illusion again--it already has a race with free Spell Focus. A Gnome who takes this feat and Greater Spell Focus is going to be feat-starved, but she'll have insane Illusion DCs.
Mastery of Faerie Enchantment is markedly strong for an Enchanter, since it Extends their entire school. With Charm, that could be enough to keep them under your thumb for the whole day, and for Dominate that will add weeks. Even Hideous Laughter becomes deadly when they have to laugh for 6 rounds at level 3.
Mastery of Ice and Fire is fine only because I figure Fireball has a long enough range anyway and Enlarge spell isn't that threatening of a feat to begin with. Scorching Ray benefits most from this.
Mastery of Madness seems like something an Alienist would want to take, but it replaces a key Alienist ability. Weird.
Mastery of Mists is niche, but it's way more powerful than anything else that deals with that niche. It gives at-will infinite use See Invisibility as a Move Action, and you can follow that up by blasting Ethereal things. Usually you have to use the Transdimensional Spell metamagic feat for that, so since you get it with a simple caster level check, this feat make Transdimensional Spell obsolete.
Mastery of the Silver Void is fair because you have to be level 16 to use it. Otherwise it will make your Dimension Door fizzle. Whoever wrote this book may not have known them very well, but those are the rules
Mastery of Twilight Denizens has a large and noticable difference for beginning summoners, since those extra rounds are crucial. However, it means they can't lead off with Augment Summoning, so probably okay.
Mastery of Twisted Shadow--20% miss chance for 1 round per spell level when you cast an Illusion spell? My Blur spell cries. This is fairly powerful, since it negates Sneak Attacks.