what were they fighting for?
To rule Egypt.
Horus
 Horus had many battles with Set, not only to avenge his father, but to choose the rightful ruler of Egypt. 
which egyptian god was bitten by a snake Horus. what is the osiris myth? It is the most elaborate and influential story in ancient Egyptian mythology. It concerns the murder of the god Osiris, a primeval king of Egypt, and its consequences. where does this myth originate from? The earliest mentions of the Osiris myth are in the Pyramid Texts, the first Egyptian funerary texts. how is horus and the god that was murdered related? Son and father. with reference to the father, what was the ritual of wheat and clay for? In the Osirian temple at Denderah, an inscription describes in detail the making of wheat paste models of each dismembered piece of Osiris to be sent out to the town where each piece is discovered by Isis. what did he look like? He was commonly depicted as a pharaoh with a complexion of either green or black in mummiform. was his cult destructed? Yes, after the imperial decrees of the late 4th century. who was his wife? Isis. where can you find her temples? Behbeit el-Hagar and Philae, to name a few. does she have any influence on christianity? Some Isiac customs may have been among the pagan religious practices that were incorporated into Christian traditions, such as the medieval Carnival festival, in which a model boat was carried, developed from the Navigium Isidis. which festival is she associated with? The Navigium Isidis and the Isia, to name a few. did her son and set have a conflict between them? Yes, they were rivals.
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Horus [SEP] Conflict between Horus and Set
Horus was told by his mother, Isis, to protect the people of Egypt from Set, the god of the desert, who had killed Horus' father, Osiris. Horus had many battles with Set, not only to avenge his father, but to choose the rightful ruler of Egypt. In these battles, Horus came to be associated with Lower Egypt, and became its patron. According to "The Contendings of Horus and Seth", Set is depicted as trying to prove his dominance by seducing Horus and then having sexual intercourse with him. However, Horus places his hand between his thighs and catches Set's semen, then subsequently throws it in the river so that he may not be said to have been inseminated by Set.