I think Sonic Chronicles: Dark Brotherhood is a game that either: not many people know about, or people quickly forgot about. It will be a surprise to many because it's a game made by Bioware, and is an RPG.
Many Bioware games were known for their dialogue and world-building, but it's really limited here. There's simplistic conversations, sometimes you have an option to get more information, but it's up to you if you want to read more text. Tails loves telling you to save the game which is also a clue that a tough enemy will appear after you take a few steps forward. However, why doesn't it just autosave? Maybe it is breaking the fourth wall, which the game suddenly does right at the end when the credits are supposed to roll.
There's some optional side-quests but it's generally very linear, although it's easy to get lost in these small areas due to the cluttered level design and confusing layout that just seems to be that way to slow you down and drag out the game length. Many areas feature tall buildings which create awkward moments when you cannot move behind them…although some you can. This means you sometimes just have to run into the sides to feel your way around. It can be hard to see how you reach certain areas because of the clutter, non-obvious or non-intuitive paths e.g. sometimes having to navigate south to find a tunnel that takes you north.
To navigate the environment, you often need to use your character's special abilities. So Amy/Knuckles will destroy boxes, Tails/Rouge can fly, Sonic/Shadow can boost run through loops (although many characters have multiple skills but sometimes weakened forms, e.g. Knuckles can also fly but only covers small gaps). Because of that, it leads to specific configurations rather than giving you the freedom of creating your own personal party. Another reason is that some battle moves require specific team members. Amy has 2 moves that require Cream. So if you don't want Cream, then you may as well bin-off Amy. When it's a party of 4 and you are required to have Sonic, it just seems limited. There are a few story moments where the team split into 2, so one team will be led by Tails or Knuckles which gives you some variety.
The game is played entirely using the touch-screen. You drag the stylus to move on the overworld, then tap through icons and menus. Sometimes there's puzzles where you are locked in a small area, and you have to switch characters and position them on switches. These are usually trial and error, or a memorisation mini-game.
Combat starts when you walk into enemies that patrol the map. Although you were supposed to gain an advantage if you walked into an enemy that hadn't seen you, I triggered loads of "ambushes" while trying to swerve out of the way of a charging enemy, so I assume the feature is broken, or just based on luck.
The battles are turn-based combat, where you can Attack, Special attack, Defend, use items, or try to flee. The normal attacks just do damage if they hit, but the special attacks require you to do timed taps, swipes, and frantically tap in order to complete the moves. Some of these moves just scale down the effects if you mess them up, whereas others completely fail which is infuriating. Tail's healing move requires 2 swipes but if you miss one then the move doesn't do anything. If successful he heals 40hp that turn and further heals on subsequent turns - so failing is just brutal.
Defending restores the PP you need for your special moves, and reduces damage taken that turn.
I found it a bit unclear what enemies are weak or resistant to, and it was hard to tell visually since many enemies look like robots but are animals in metallic suits. Weaknesses and critical hits seem to make a large difference too.
Many enemies are infuriating to battle - many enemies with high defence or use "Evade" or some kind of defensive block, there's a type of robot that regenerate unless you defeat all enemies in that turn, then robots that self-destruct and will most likely kill your character unless they have full HP and have a large amount of HP too.
Sometimes the enemies try to flee, and then you play a minigame to jump over obstacles whilst chasing them, gaining ground when you run over a boost pad. It can be too easy to swipe on the wrong character due to the lack of screen space and timing required.
When you want to use items in battle, you just see a list of names rather than seeing the descriptions of what the items do like you see outside battle.
When you level up, you get to choose one of your attributes to boost by 1 (strength, defence, speed, luck).
There are chao eggs to find which can be equipped for a certain effect eg add/defend elemental damage, boost PP, heal per turn etc.
Sonic Chronicles has too many frustrations and half-baked ideas to recommend. I found it a chore to play. You may think it would be a good entry-level RPG for children but I think it could be too difficult and frustrating for them to enjoy.