BitmapFontCache class supports in-string colored text through a simple markup language. font.getData().markupEnabled to turn it on/off. The markup syntax is really simple but still versatile:

• [name] Sets the color by name. There are a few predefined colors, see the Colors.reset() method for an exhaustive list. Users can define their own colors through the methods of the Colors class.
• [#xxxxxxxx] Sets the color specified by the hex value xxxxxxxx in the form RRGGBBAA where AA is optional and defaults to 0xFF.
• [] Sets the color to the previous color (kind of optional end tag)
• [[ Escapes the left bracket. # nor [, and cannot contain ]. Also, any occurrence of [ in the color name must not be escaped. Unknown colors, illegal hex codes and unclosed tags are silently ignored and treated as normal text. BitmapFontTest. Note: When using with Scene2D you have to remove the fontColor property from LabelStyle definition in the skin.json file to have markup coloring work with a Label.