• Can edit levels, backgrounds tiles, stairs, sprites, palettes, monsters, candles etc.
• Some limitations with editing entity monster, candle data for horizontal levels as the data is shared between levels.
• Clocktower certain parts you can't edit without a hexeditor or ASM.
• Some bosses can't be edited, moved to other areas without code modification.

Support for Japanese version is very poor. A lot of things can corrupt data like stairs, doors, wall items, music, bosses, curse severity, random crashses etc. A few areas have bugs the US version doesn't. After a certain point you'll get a fatal error message rom has been corrupted, and you can't edit it anymore in Revamp. Wouldn't recommended editing Japanese version unless you know ASM, and are comfortable with manual editing.