I want to try to fight Marlix, but I just don't know how to find/summon Him. Any tips in the comments would be helpful. Thanks.
My tip to find him: ● Run with your horse from spawn to spawn (in the wasteland). My tip to kill it: ● Do NOT use fire asspect on the item that you're using. (If the marlix dies from the fire you WONT get any drops). I hope this helped you out. (I know not the best options but it helps)
As pascal said, the best way to find him is just running around. He'll spawn randomly, but is very rare.
I ran into one today it was funny looked like a jock just cruising in the air. I only had a stone sword and was trying to get back to spawn so I guess he is still flying out there somewhere...