Holy Avanger Sidius (demo) is a well-rounded campaign that may be worth the time to play if you are eager for some RPGs.
The playability for this campaign is average, to say the most. There were some bugs such as loopable dialogues and spelling mistakes. My biggest complain in this area is the lack of instructions. There were no pre-scenario instructions at the beginning of the campaign, nor were there any detailed instructions given throughout the game. This frustrated me since a lot of times I had no idea on where to go. In addition, the character that you control has the same player color as your ally. This will tend to confuse some people, especially at the beginning of the scenario, on who's your main character.
The balance was just right in my opinion. None of the "pack" of enemies you encounter will be easy to defeat. The last leader of your enemy, especially, will need some strategy before you can beat him. The author had also offered a secret item to boost your character's stats if you have trouble, but you have to find it first as a side-quest.
Creativity was nicely demonstrated in this campaign. Similar to most RPGs, you can talk to the friendly natives just by 'clicking' on them. Also as I mentioned, there is a side quest if you find the campaign too difficult. It was also nice to see your character start as merely a weak and helpless Villager. Only after completing several quests will you eventually turn into a solid warrior. The only negative comment I will make, which made me give a '4' instead of '5', is the lack of enemy types. After exploring the whole map I have only found 2 or 3 types of enemies and wolves. It can be boring to fight the same type of enemies all the time.
The author has undoubtedly put a lot of effort into the map design. The mixture of different terrains and eye-candies put together has made this map look very beautiful. The buildings are all naturally placed, forming realistic countryside towns.
Since the author classified his campaign as an RPG, I expected some basic storyline. There wasn't any, unfortunately. You weren't provided with any history or character background at the beginning. Instead, 3 quests were thrown to you immediately, requiring you to find help yourself. What lowers this area's score even more is the lack of instructions. Even though at the beginning you have 3 quests no obvious help or directions were given on how to accomplish the objectives. This is definitely the weakest area in this campaign.
Overall, this is a very good RPG campaign. Since this is only a demo, I am sure DarkDragonTeam can still tune it up, especially on the instructions area. At the current stage, however, I would recommend it only for RPG fans to try it out. Others may get more frustrated at the lack of instructions.