Super NT
Number theory practice for experts, combining problems from Exp and Heavy NT as well as some other sources.
This is a bit of a mixture of all the "fundamental" number theory topics related to Diophantine equations: orders modulo a prime, polynomial equations, and quadratic reciprocity. Its content is essentially all from Expon NT and Heavy NT, and as one might expect its problem set also has substantial overlap with them, as well as some problems related to the Size in NT and Euclidean Algorithm units.
It is one of the hardest NT units, though not quite as challenging as N7 Summit. The unit contains extremely difficult questions such as this diophantine equation from the expon section and ELMO 2013/3 from the size/euclid section.