Drink from thy cup and heal thy soul.
I hadn’t realized this until now but Fountains in the dungeons can heal HP’s of your party members. However, sometimes…fountains can disperse poisonous water.
I thought that since the fountains could regenerate HP, that perhaps Thrones could possible regenerate SP? but even upon getting a positive energy absorption, that it would regenerate SP, but No. It apparently does not. At least, not to my knowledge. I’m not sure what it does at the moment. I do know that many thrones give ZZAPP’S! (HP damage) to many that dare to sit on the throne. I’m sure I’ll find out eventually.
Edit: OK I’ve figured it out now. If you sit on a throne and it doesn’t ZZAPP you, you will get one of your stats (STR, INT, WIS, DEX, CON, CHA etc) modified randomly by either adding +1 or subtracting -1. Ruby now has 21 for INT instead of 20, but upon sitting atop the throne another time, STR has decreased to 14 from 15, so I guess if you want different stats for your character you can take your chances on the throne. It might help or hurt you. Roll the dice.