The idea is that the computer is playing a tactics game to win, but you, the player have to manipulate the game events - the ones you control - in order to fulfill the reenactment criteria. For instance, the mission is over when you reach 50% casualties, so you can rather than act defensively, by purposely being reckless, you can increase you casualty count. Similarly, you can sabotage a cannon so that it misfires at a critical moment.

So the game is somewhat a typical tactics game, where you are trying to achieve certain goals by a certain round, or in a certain order, and need to play smartly to do so. It is also a game about manipulating the battlefield, sometimes intentionally losing to throw a battle or manipulating the enemy AI into performing specific actions.

Fig 215.2 - Big Book of Highlights.

That's good and fun by itself, but what if your reenactment criteria looked like this:

I think it would be cool if the game didn't explicitly state what the goals for each mission were and instead forced you to look it up. My idea here is that there is a history book (or perhaps several) which cover the war and each battle, which you have to read in order to discover the criteria. Maybe the books have different information, or perhaps critical information is kept in different chapters.

While you are reading the history books, you can highlight text passages that you think pertain to the reenactment criteria. For instance, you could highlight "Hero was the sole survivor of this battle" from a book about Hero's life and "The sole survivor of this battle managed to escape by pretending to be dead" from another history book. Highlighting these two passaged will unlock the criteria for that bullet point:

Perhaps there could even be hidden, bonus criteria to unlock for the careful historian.

Not only could you unlock criteria bullet points, you can unlock special abilities and bonus events by highlighting the right passage. For instance, highlighting a passage about a stomach illness plaguing the camp and you'll unlock a dysentery event where half your soldiers begin at half health and lowered accuracy, thus making it easier to lose 50% of your troops without accidentally killing the enemy first. Or maybe highlight a section about how the battle took place near a farm, causing farm animals to flood the field, preventing enemy soldiers from checking to make sure that dead soldiers aren't just pretending.