Twelve-Winged Dark Seraphim
I feel like the Primordial spore like thing is the best guess. Maybe it has a similar unkillable life providence and parasite abilities, or just high damage abilities with the unkillable life providence due to how small it is? If so, he could just toss Tai Su at that thing with less than 2 hours left and win, without having to face a challenge from other people due to how weak Tai Su is.