A donkey that can speak? The prophet Balaam had such an animal, at least on one occasion. As the Israelites journeyed from Egypt to their home in Canaan, they passed through the hostile land of Moab.
The Moabite king sent his prophet Balaam to place a curse on Israel. God specifically told Balaam not to do this, but he rode out anyway, and as he rode toward the Israelites his donkey veered off, and Balaam beat her, not seeing the angel himself. The poor beast finally lay down, and Balaam beat her again.
This time she spoke:
“What have I done to you, that you have struck me these three times?” (Num. 22:28). God then opened Balaam’s eyes and he saw the angel and fell facedown.
He changed his plans (naturally), and instead of cursing the Israelites, he prophesied that they would be a great nation, blessed by God (Num. 22–24).