> og komst í skotfæri við hann og skýtur til hans

spjóti og í gegnum hann.

> and he came into shot-range of him and he shot at him and the

spear went through him

'skjóta' "to shoot, throw; thrust" takes dative for the missile, so
literally "and throws a spear at him and through him", which we could
paraphrase as "and throws a spear at him, piercing him", or something
like that.