後方の砲兵部隊の突撃準備砲撃は、未だ止むことを知らない。 砲身の過熱も厭わず、陣地転換の間さえも惜しんだ猛砲撃だ。絶え間なく大地をどよもす大口径榴弾の炸裂音の中、楔型陣形を組んだ機甲部隊の〈ヴァナルガンド〉が前進を開始。瞬く間に最高速度に達して驀進するその背後に、追従する影のように歩兵戦闘車が続く。
パワーパックとエンジンの兇暴な雄叫びを鬨の声と上げ、鋼鉄の濁流が薄明の戦野を疾走する。
86─エイティシックス─Ep.3 ─ラン・スルー・ザ・バトルフロント─〈下〉 安里アサト
Does the bold と function like に (with…as…) or として (as)? If not, how should I understand this usage?
First, let me say that this usage of と is noticeable even to native speakers who have read dozens of modern novels. Still, if I have to analyze this, I would take this as the "と for resultant form". This is probably the same と as in 露と消える, 無用の長物と化す, 災い転じて福と成す, etc. That is, the sound of the engine ended up being something like a war cry (鬨の声). In modern Japanese, this type of と is usually found mainly in fixed phrases including the ones listed above. It would look very stilted if used outside fixed phrases.
Another possibility is "と for similarity" in classical Japanese; according to 古語 dictionaries, と meant "like ～" in the past (e.g. 秋風と聞こゆる = 秋風のように聞こえる). But I feel such a usage was not very common even in the past.
You have asked a similar question from the same novel: Do both と and に mean "become" here?
