You could continue the diagram by adding quaternions and octonions as further supersets of complex numbers.
In addition, cardinals and ordinals are alternative ways of extending natural numbers, and p-adics are an alternative way of extending rationals into reals and beyond.
I do remember a little bit about cardinals, ordinals, countable sets, and uncountable sets from set theory.
I am not familiar with p-adics.
Even though I did learn a few things about complex numbers a while back such as Liouville's Theorem, line integrals and Laurent series, I have never heard of quaternions nor octonions.