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Abstract. We prove that a balanced 8-round Feistel network is indifferentiable from a random per-mutation. This result comes on the heels of (and is part of the same body of work as) a 10-round indifferentiability result for Feistel network recently announced by the same team of authors [10]. The current 8-round simulator achieves similar security, query complexity and runtime as the 10-round simulator and is not significantly more involved. As such, the security of our simulator is also slightly better than the security of the previous 14-round simulator of Holenstein et al. [18] (O(q8/2n) vs. O(210/2n)) for a comparable runtime and query complexity (these metrics being both O(q4) in bot