First Edition Feats is an eleven page PDF two of which are taken up by a full color cover and the OGL. The contents are just what you would expect. It adds a feat system, except it calls its feats combat proficiencies, to 1st Edition AD&D and OSRIC. It should be easily adaptable to other versions of D&D with no or little work. The biggest issue for D&D as opposed to AD&D is it is based on the weapons proficiency system. Adopting it to the BECMI/RC weapons mastery system would be easy and either of those could be grafted onto the rest of the family.
The rules on combat proficiencies take about two pages of rules including design notes. It allows a character to substitute one of the combat proficiencies for a weapon proficiency. Each combat proficiency can be taken twice for two levels of effect. The rules require a character to take at least one weapon proficiency and prohibit the doubling of a combat proficiency at level one. The system recommends that monsters of at least low intelligence have access to the system at up to one combat proficiency per 2HD and requiring at least average intelligence to take a double proficiency. I can imagine an orge or orc shaman with a couple of these spicing up a combat.
The rest of material describes twenty-one combat proficiencies. Each has a name, one sentence description, prerequisite, class, single proficiency benefit, and double proficiency benefit. The prerequisites are generally ability score values or weapon proficiencies although there is one alignment prerequisite. Most of the abilities provide a small bonus under certain circumstances. For example, the Two Handed Weapon proficiency adds +1 to damage when using a two handed weapon. Shield Bash allows you to sacrifice you shield's AC bonus and use your shield as an off hand weapon. The only magic-user allowed proficiency allows magic-users to use a single type of magical weapon where the weapon type is not normally allowed but unable to use the magical abilities unless they take the double proficiency.
The proficiencies occasionally have two additional entries. Special gives notes outside of the above. For example the special section on the Archery proficiency notes you can use more than one slot on the double bonus, which is bow type specific, to use it with another bow type. The second section is called Normal. This to me is what makes this a true old school product. A common complaint against feats and skills in the OSR is they are limiting. If your character lacks feat X then they can't try to do that. While a valid complaint I think this is only half the story. As I've written before old school characters are made out of what they're good at doing. By supplying a normal rule for proficiencies which don't have rules already in place this supplement emphasizes the fact they are about what you're good at doing and not "permission" to do something.
While I have some quibbles, such as not opening up the special staff abilities to magic-users, in general I think this was worth the cost. I bought it for a proposed 2nd edition game and would probably use it with everything from that to Labrynth Lord. It is low impact in terms of time added to character creation and game play. It helps provide mechanical differentiation to the one class in older versions of D&D that really needs it, fighters. In fact, if you're in an older game with a dozen different fighter types you might be able to prune it some if you'd like. Finally, it provides a good outline to Dungeon Masters and players wanting to add their own unique abilities. If the publisher were to revisit it the one thing I'd like to see is a single page summary chart of the combat proficiencies.
I'm not as enthused about 1E Heroic Abilities. It is a mere six pages, again two used by the full color cover and OGL, and provides three related expansions to ability scores. First, for each class it defines certain abilities as having secondary ability scores. These are decimal scores identical to and generated in the same manner as exceptional strength. Roll percentiles for three ability scores for your class and list them in the traditional format: XX/yy. Once per day per level a character may roll percentiles against a given scores secondary ability and success allows you to treat it as the next highest value. You cannot use this to raise hit points or gain bonus spells.
The second usage is when the character has a base 18 in their prime requisite. For those characters it provides tables for 18/xx bonuses for the three ability scores which are prime requisites and don't 18/xx bonuses in the core rules. Dexterity adds to thief skills. Intelligence add languages and increases the chance to know spells and save versus illusions. Wisdom provides spells, additional magical attack saves, and magic resistance.
The final usage is to increase ability scores. At each level a character gets three dices pools of 3d10, 2d10, and 1d10 to add to there secondary ability scores. One must be assigned to each of the abilities for the class. If the total exceeds 100 you subtract 100 from the secondary abilities and increase the primary score by one.
This system isn't that different from those common in 'zines back in the day or even that in Hackmaster 4th edition. It's not as unique or compelling as First Edition Feats. I wouldn't recommend it as a separate purchase although if the two products were folded together and the price set at about four dollars I would recommend the combined product.
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