I made two max petamions from scratch and I can say it is not so hard and in several weeks you might make one (trying maybe with two characters). The second is harder as I think the game can have a mechanic to check if you got the rare drop before and if you did it make very very rare.
Also about the main topic thing, I also tried several weeks to make one terralion and I made at least an interesting observation. Like the farm thread points differents places to farm gems or items, some are better for one server than another due as an channel becomes crowded it also makes more and more mob to appear and making easier to drop the item. So , crowded channels could have more mobs to kill and also more white mob (that worth 100 mobs ) to appear.
By the way my server the map was only me an I think I tried a month and I didn’t even get 10, even killing many White mobs that didn’t drop it which is very frustrating and I even made a support ticket about it