Chinese culture has a yearly family ceremony tradition to honor their anchestor. The ceremony is quite elaborate as there will be paper money burning, for richer family they'll also burn paper luxury houses, handphones, cars etc and a various dishes and fruits, water and rice on the altar along with joss sticks. Family members will take several joss sticks and make their prayers in front of the offering altar and ask the anchestor for protection, health, wealth and whatever they desire. And then wait for a few hours after that to let the spirits to feast on the offerings. They'll "dispose" the abundance of food afterward by eating it themself unlike the practice of other traditions.
In Indonesian culture, especially the Javanese and Balinese, making their offerings consists of 7 types of flower - usually called "Kembang Setaman" translated roughly as "Whole Garden Flowers", a coconut, rice and incence. The offerings and amount of it usually differ depending on the purpose of a ritual or ceremony.
That's mostly what I know about offerings, and their practices. I'd be interested to learn more on what knowledge can you share or what do you offer the spirits (in necromancy/evocation/worship practice)
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