When Melanchion is given the 3 quest objects, there is no message to confirm any gains for the characters, contrary to the boon in melee weapons received from the Trainer Shade.
The 1st time they met Melanchion, they had all 3 objects, so they give them all right away. No gratitude.
I replayed that encounter, and if the characters left the castle the only gain that happened was Resistance +1 at the 1st item given, for the only character that still had no Resistance (the others had some from equipped items) but still no message.
Then, even going out of the region through the teleporter, there were no gains in Strength, Dexterity or Intelligence as the 2nd and 3rd items were given.
Is it a bug? Is there some other action to perform (as if collecting these rarities and giving them away was not quite enough)? Does it take action later, at some other event? Is it a boon only for those characters that have 0 in special skills or are somewhat lacking in basic skills (like lack of Strength, i.e. encumbered, did not test that possibility yet)? Is it dragon greediness?
?
Thanks to Synergy for his LIST: Avernum 5 Items (Who, What, and Where)