Aura RPG for the TI-83+, developped by Dysfunction from EPS is currently progressing nicely. Here is a screenshot:
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As you can see, it features complex sprite masking and it run pretty fast for BASIC (YES! This is in BASIC!!!). The author plan on adding a real-time battle system like Tales of Phantasia. Visit the forums for more info.
Digitan on UnitedTI forums announced that Robo War for the TI-82 is almost complete. Now he plans on optimizing the game so it can fit on the 83 serie.