If you’re looking for a supplement that adds a level of grit to your 5e campaign, this is the product to get.
All of the General Combat feats are thematic and tactical. Want to extend your critical threat range? You’re covered with the Critical Hitter feat. Some feats, such as Rending Gash and Signature Maneuver even boost the die type of the weapons you use.
Skill Mastery feats are an interesting expansion on the existing skill structure, applying ability bonuses to certain stats based on skill proficiencies. You also gain advantage on checks linked to the skill.
Weapon Style feats are pretty cool, allowing you to focus in improving your combat mastery with different types of weapons (Heavy, slashing, piercing, etc.). I think this section could have been fleshed out more, but the existing feats are great.
The new Boons are appropriately combat themed. You can do things like turn a normal attack into a critical hit, deflect damage, or even deal ongoing damage.
Combat Maneuvers are sexy. You can apply new conditions to a foe, such as gushing wounds, internal injuries, and even the loss of limbs! I wish there were more of these.
The Called Shot rules are wicked slick. Their execution is simple (on a successful hit, a Saving Throw determines whether or not the effect is applied) and the effects easy to manage without having to remember a ton of new conditions. Too many game designers try and introduce called shot systems, which end up being little more than table after table of specific effects. Detail is fine, but too much detail slows the game down. These rules don’t. Well done.
I think the new backgrounds, and the class options are cool, and provide interesting options for character creation without being redundant.
Two new conditions are presented: Battered, Bloodied. I think these are definitely worth integrating into your game if you wish to reflect the idea that characters get progressively weaker as they sustain more damage in combat. Helpless is listed in the conditions section, but I’m not sure if this is a new condition or not, as there doesn’t seem to be anything that triggers it.
Overall, very good supplement, especially for the price. There are a few issues with formatting that I would like to see cleaned up, but they aren’t deal breakers. The artwork is good and thematic.