Rescuing dragons is a rather simple kill-all-the-bad-guys type thing. When your party comes across a dragon in danger of being kidnapped, or when your party reaches Shadow Hold and finds imprisoned dragons, your duty is to get the dragons out of danger by killing all the bad guys. Your character would use the d20 to use their skills like “weapon” or “throw/catch” or even “dodge” to take everybody out. Abilities can also come in handy!
Every bad guys has 5 hit points. Theoretically, you could take one out per turn. However, bad guys also have two skills marked at 5 as well: dodge and weapon. This means you need to be able to hit the guy and also role high enough on a d6 to do some real damage.