Adventures are activities that offer variety from the constant grind of the hero's life of questing and drinking. They are rewarding and interesting in their own right, and are also needed for the completion of have adventures side jobs. Different adventures count in different ways for the side job and for the Pantheon of Adventure.
A guild member's adventures will only contribute to that guild's Pantheon score if they are of rank Chief Master or above.
Kinds of adventure
Sending the hero to the arena to duel counts as a side job adventure. It doesn't matter if the duel is AFK, nor does it matter if the hero wins the duel.
Sparring with a friend counts as a side job adventure for both friends. It doesn't matter if you have duelled the friend before, nor does it matter who wins the duel.
Sparring fights do not count as an adventure for the Pantheon of Adventure.
A fight with an aboveground, mini-quest, or dig boss counts as a side job adventure. The boss fight can begin at random (as a mini-quest ending, as a rare encounter while donning an aura of hunting (?)), from an activatable artifact, or from a "dig" command. Note that boss fights as part of a dungeon do not count as an adventure of their own.
Note that a mini-quest itself does not count as an adventure.
Boss fights do not count as an adventure for the Pantheon of Adventure.
Entering a dungeon counts as an adventure. The dungeon, including any boss fights, is all considered to be a single adventure, regardless of success or failure.
An unsuccessful dungeon counts for one point in the Pantheon of Adventure, but a successful dungeon counts for three points.
Embarking upon a sail counts as an adventure. The sail, including any beastie or pirate battles, is all considered to be a single adventure, regardless of success or failure.
Embarking upon an unsuccessful sail counts for three points in the Pantheon of Adventure, and a successful sail counts for nine points.
Sending the lab boss into a datamine counts as a side job adventure, regardless or success or failure. This is the only adventure type that isn't performed by the hero.
Datamines do not currently count towards the Pantheon of Adventure.