Found this cute snippet in the Makefile of the NumWorks Epsilon codebase. It is a rudimentary implementation of the cowsay functionality.

We also see how it is used in the clena: cowsay_CLENA clean part.
I like how it reminds about the typo when calling the clena instead of the clean target.
It gives a clear but unintrusive message about the typo, and then also does what was intented (running the clean target).

.PHONY: cowsay_%
cowsay_%:
	@echo " -------"
	@echo "| $(*F) |"
	@echo " -------"
	@echo "        \\   ^__^"
	@echo "         \\  (oo)\\_______"
	@echo "            (__)\\       )\\/\\"
	@echo "                ||----w |"
	@echo "                ||     ||"

.PHONY: clena
clena: cowsay_CLENA clean