In the span of less than a month, the strength of the three-headed Divine Beast had increased a bit, indicating that at the very beginning, when the Divine Beasts had just broken free, they definitely weren't as powerful as they are now.
That is to say, if Zhou Tian hadn't indulged in hundreds of years of pleasure and caused his own combat power to decline drastically, if Zhou Tian had encircled and attacked those Divine Beasts from the beginning, then taking his original strength into account, it's not just the three Divine Beasts – even if four Divine Beasts had gathered together, they ultimately wouldn't have been able to stand as his opponents.
Meanwhile, if Zhou Tian had shown the same performance as he now possessed from the beginning, without losing the Short Sword, Zhou Tian would have succeeded against the three Divine Beasts earlier by several months, and he wouldn't have struggled to subdue them. With such thoughts, how could Zhou Tian not feel regret?