The main difference with the RPG mode comes in the addition of inventory and skill systems, which aren't as involved as what you'd expect from a dedicated action RPG, but they do add some options for developing your character as you gain experience levels. The seven characters are straight out of the main game and start off weak enough that fighting packs of wolves, bears, and skeletons can be a challenge even on the easier setting. Making it through solo battles means popping health potions and taking advantage of the many magical health stations scattered around, but there are a variety of hirelings available to help you out if you have the cash.
The RPG scenarios take place on dense maps packed with random encounters and villagers ready to sell a variety of items and hand out quests. The obvious focus of any action RPG is on fighting monsters and on building up your character, but unfortunately the game's engine is better suited to RTS-style battles. A character can easily find its path from one edge of the map to the other, but doesn't move responsively in close combat. Clicking on an enemy to have a spellcaster attack with a lightning staff may result in the character dancing around, wasting time as a monster closes in, instead of firing at the weapon's maximum distance. On the other hand, melee combat is terribly automatic, so there's not much direct action. The maps are also so tightly packed--much more than the RTS maps--that they provide little room for satisfying exploration and seem less like a part of a fairy-tale world than an abstract exercise.
The RPG mode limits you to sending a single character through gauntlets of monsters.
Even if the story, and the long-winded cutscenes that tell it in both parts of the game, wasn't dull and clichÃ©-ridden, the leaden voice acting and uneven tone would still weigh it down. Most of the developer's comedic effort apparently went into writing odd things for units to say as they move around the map. While Sir John is almost competently voiced, he's given odd sayings like "We shall not stand for anything the enemy has to offer" and "We're just standing around and time is running away," which are more nonsensical than anything. And even if these voice clips don't annoy you by the end of the three main campaigns, they're rather more painful in the RPG mode, since you only hear the limited selection of things one unit has to say as movement orders are confirmed. By comparison, the graphics may seem quite good, particularly the water effects. But even this technical proficiency is undermined by maps that just aren't very interesting to look at.
In a fairy-tale world, Once Upon a Knight could be recommended for offering two games in one box, but in reality, neither is very good. The story missions may take quite some time to play through, but there's little to motivate you to do so. And even the skirmish mode, which you might expect to highlight the game's strategy strengths, is hobbled by poor AI. A single computer-controlled player isn't much of a challenge, and multiple CPU players will gang up on you without fighting each other. Furthermore, at this time, it's quite difficult to find anyone to play a multiplayer game with on the Earthnet matchmaking service. It's hard to find any part of the game that's truly entertaining.