Although Zhou Tian seemed to have no difficulty in killing the elephant, this did not mean that the elephant was weak. In fact, if it had been any other living being encountering this elephant, they would indeed have been easy prey.
Who would have thought that this seemingly docile elephant was so cunning, feigning a lack of readiness only to lure out its enemies? The attacks it knew were highly deadly, and only because Zhou Tian possessed an immortal body was he unharmed. Had it been any other living being, they would likely have been dead the moment they fell for the first attack.
So, what did it matter if the elephant's weakness was obvious at that time?
As soon as the elephant's enemies appeared, they would be struck by its attacks. Given the elephant's strength, any being hit by it would certainly have died at that moment. If they were already dead after being hit, knowing its weakness would have given them no opportunity to exploit it.