The only illustrative reference is from Ancient Warfare magazine but it is a sketchy simplification : The boat was submerged with blacksmith tools, with wooden vessels and recipients, animals were sacrificed, notably a horse and two dogs. Spears and oars were thrust into the silty bottom to anchor it. There were dozen of spears and shields submerged with the boat.  

So maybe a wonder could look something like that? Do you have further references? without the heap:  

@nifa The only idea I can have specifically about the Cimbri, is the Hjortspring deposit. The boat was deposited in a small bog of approx. 50 m in diameter, in the middle of an island. I don't know if it is more practical.

I don't know. But I know the Germans from this time period didn't make new burial mounds, because they are practicing cremation, deposing the ashes in urns, which are then buried. At the best, they used older mounds to bury their urn in the upper layers. 

Hi! I know this was probably asked lim -> infinity times: which are the parts that takes most of the computational time and contributes mostly to lag? Simulation? Pathfinding?