I ended up partying with fellow saato+ members (and few others) and we started by killing Witch-king and then later Artemis and Golux from Great central desert. I didn’t have area quest from GCD, so got that at the same time.

Melcross BOOMS 'Well done, you have brought me all the pieces. As
a reward I shall give you the axe forged by the smith deity, Marion!'

Melcross draws a pentagram to the floor with blood and places the
items inside it while chanting a strange hymn. Suddenly the pieces
start to twitch and begin to draw together.

The items touch together all as one and with a mighty thunderclap
they meld into a strangely glowing axe. Grinning devilishly
Melcross picks up the axe and hands it to you.
Congratulations! You have just completed Melcross!
You receive 57604 gold as a reward for completing the quest.
You receive 6 training points.

From the trip, I got Rod of Artemis and Ancient book of knowledge, which I probably save for some other reinc.