Although this experiment was not the outcome you most hoped to see, it was not the worst-case scenario either. After all, while battles between powerful cultivators could drag on, the moment that truly decided life and death was often but an instant; even a single second was enough to kill one's opponent countless times.
Being able to rewind fifteen seconds was already enough to avert the vast majority of situations unfavorable to you.
And if rewind was used in battle, you would learn in advance the changes that would occur during that time, as well as the moves your opponent would make. This was an enormous advantage. Combined with the Insight of your Double Pupils, this ability could be pushed to its utmost limit.
Moreover, the rewind ability could, to a certain extent, prevent you from being caught off guard by an enemy's killing move in battle. Once an enemy's hidden killing move proved too powerful and posed an immense threat to you, you could rewind.
And once you were on guard, the threat posed by the other party's killing move would naturally diminish greatly. At worst, you could escape before they unleashed it.
Furthermore, as far as you knew, aside from some Dao Fruits, the strength of most Dao Fruits was inextricably tied to their owner. In other words, the effects of rewind were not set in stone. As your cultivation realm improved, the amount of time you could rewind would increase, while the price you paid would correspondingly decrease.
So, it was not that the rewind ability was inadequate, but that your current cultivation realm was insufficient to bring out all of its power.
Of course, the current rewind ability was still extremely useful to you. Aside from using it in battle, after several experiments, you discovered that