Based on two plays with novice wargamers just outof the box, I have to say that I think Napoleon's War: The 100 Days succeeds as an entertaining light wargame suitable for sucking in new players while being enjoyable for grognards as a filler game.
Based on the same general system as Hold the Line, Clash for a Continent and For Honor and Glory, Napoleon's War: The 100 Days is roughly the same level of complexity. While it has a few special wrinkles (such as infantry squares and skirmishers) to reflect the changes in warfare between the linear warfare of the earlier games and the Napoleonic era the new rules are straightforward and introduce minimal complexity to the design.
The more involved rules are added as "intermediate rules" and can be left out when playing with new players. The most involved rules are presented as "Kevin Duke's Advanced Skirmisher Rules" and take up nearly a whole page of the 8-page rulebook, but in truth they are still pretty simple by wargame standards and I expect that experienced wargamers will use them.
The heart of the game system is the use of Command Action Points. Each player starts with a base number of CAPs (typically 4) and adds 1-3 more CAPs based on a die roll. Each CAP can be used to activate a single unit to move or fire. An additional CAP can be expended to allow an infantry unit to move again or to allow and infantry or cavalry unit to charge into shock combat.
Combat is resolved by rolling 3 dice with "sixes" generally inflicting a hit. Artillery firing at close range and infantry and cavalry in shock combat have an increased chance to hit, while certain terrain effects and other conditions may add or subtract dice.
Hits remove figures from the target unit, similar to the system used in Borg's Commands & Colors system. Higher quality units such as British infantry have 4 figures per unit while more fragile units such as most cavalry, artillery and Dutch-Belgian infantry have just 2 figures. Regular infantry has three figures. Some units such as Heavy Cavalry and Elite infantry get a chit that essentially can absorb more hits. I found this the least graphically satisfactory element of the design. It seems less elegant than simply having more figures would. Leaders are also represented by cardboard counters instead of figures.
The figures themselves are nice, although generic, busby-wearing infantry, cavalry and guns in hard plastic. The nations are differentiated by color, blue for France, Red for Britain and Grey for Germans.
Unlike the Commands and Colors games or the earlier games in the Hold the Line series every battle in Napoleon's War comes with its own map, instead of a blank map and terrain tiles. This makes set up a little easier but reduces the scope for player-designed scenarios. The maps themselves are double-sided on sturdy card stock. The maps do not link and can't all be used at the same time Napoleon's Last Battles style.
The unit, ground and time scales are all undefined and vague as is the usual style with this sort of game. Instead each scenario is set up to give each side around a dozen to a dozen and a half units. At Waterloo, for example, each infantry unit appears to represnt about a division while at Quatre Bras they seem to be brigade-sized.
As is unfortunately often the case with small publishers, the rules seem to have needed a little more proofreading. There are some misspellings ("Belgiam"), unclear scenario rules (reinforcement entry ares in Quatres Bras and how CAPs are allocated between allies at Waterloo) but nothing an experienced wargamer can't work through.
There are plans for additional games in the series that will bring in the Russians, Austrians and Spanish and scenario packs with more maps, but the basic game provides a nice introductory 4-game set of wargames. I had no trouble explaining the rules to two nonwargamer players who were able to play competently and enjoy the game on the first go. Playing time seems to be well within the 1-2 hours promised by the box so you can probably play all four battles in an evening's worth of gaming.
All-in-all I'd recommend this to anyone who has enjoyed Worthington Games' earlier games or Borg's designs.