User blog comment:Baselhumos/HxH Questions and Discussions/@comment-14902757-20140921221955/@comment-14902757-20140922182241

You're welcome.

3. Enhancers tend to use their abilities to look younger. As shown in both anime and manga, and as described in this wiki, Maha's appearance has deteriorated due to old age. That might mean he already lost most of his vitality to even afford to look young. I would assume he's still capable but things like endurance and number of powerful attacks he could land would have already decreased tremendously. Using powerful abilities would most likely cause fatigue to his old body, so maybe his remaining strengths are now reserved as last resort kind of thing. Otherwise, he's just there to provide backup and will later on die a natural death... With Alluka and Killua around though, who knows? Maybe he could be young again.