They don't receive gifts or geas (that implies they can't learn the Sense Assassin skill).
They can learn a special skill - swashbuckling - and a special spirit
spell, Long Blade. Both resulted from the games that durulz played with
Humakt.
The skill emerged as the natural way for durulz to fight given their
small size and their high agility. The spell was created by Humakt in order
to make things more even and give durulz a chance of winning when playing
duels with him.
They are treated as initiates of Humakt if they don't have any friendship with Eurmal. They can apply for formal initiation if they fulfill the requirements.
A Blade Friend can learn Detect Truth, Morale, Oath, Berserk, Shield, Truesword and Sever Spirit like Sword Lords. He can learn Turn Undead one-use but the durulz must specify the undead he wants to turn and the spell can only be cast upon that particular undead.
If he fulfills all the requirements for Sword of Humakt, and he isn't a Friend of Eurmal, he can apply for that status.
Blade Friends can become Humakt Friends for Death if: in the course of a shamanic Five Duck Friends ritual where the spirit of Humakt is summoned the Blade Friend commits suicide with his favored sword or blade, assisted by other Blade friends; or if the Blade Friend dies fighting with a blood tainted blade in hand.
The damage modifier is increased one level (that means, if the durulz has a damage modifier of -1d4 in normal sword attacks, the modifier will be 0 in swashbuckling attacks).
The swashbuckler can only attack AND parry if the adversary is also swashbuckling. If the enemy is using a different fighting skill and the swashbuckler wants to attack he can only defend by dodging the enemy's attacks.
'I don't understand why you humans call the lifelongers undead. This word is completely meaningless, doesn't say anything. What is a lifelonger? Think about it this way. There are people that don't accept that they are getting old and that their youth is past and gone. They keep dressing and behaving like if they were kids. Yet, Yelm turns only in one direction he doesn't go back. Most of the time they simply make fools of themselves. Sometimes they became an annoyance and even dangerous. Lifelongers are just like that. Their life is past and gone but they act like if it would last forever. Why should you bother with them if they don't disturb you?'
I replied that I didn't understand how him, a Blade friend could keep his friendship to Humakt and go along with undead:
'That's the essence of friendship, respecting your differences. I strongly agree with the great Humakt that either you're alive or you're dead. And when I die I expect to become a Friend for Death of my blade's master. But why should I make my duty to ensure that everybody thinks like me? If someone wrongs himself into believing that he can retain life after death, why should I bother? That's the matter for jokes, not for strokes.
(After a pause he continued) Now, if someone turns your dead friend into a lifelonger, why should you be mad with your friend? It's not is fault. All you can do is to try to help him getting rid of the sickness.' "