RLC2 files are also known as Image Systems RLC2 Graphics and represent a rare format that most likely can't be opened using regular image viewers. In case you found such a file and want to open it, it's probably best to convert it to a more accessible extension.
The quick and simple way to handle your files is to get a quality piece of software, such as reaConverter. This software is extremely efficient in managing a wide range of batch conversions. As you will soon realize, reaConverter will help you avoid spending countless hours trying to figure out how to convert multiple RLC2 files as once.
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