Who is the Roman senator and general who instituted a number of military reforms around 90 BCE?

Answer is within the following vocab:

Cyrus the Great

Archimedes

Constantine I

Darius the Great

Hoplites

Homer

Satraps

Sparta

Virgil

Claudius Ptolemy

Legions

Etruscans

Zoroastrianism

Spartacus

Julius Caesar

Ahuramazda

Marathon

Octavian (Augustus Caesar)

Olympic Games

Plato

Sassanid

Pericles

Phillip II

Paul of Tarsus