Assyria converts military conquest directly into a technology lead — every Settlement it captures for the first time hands over both a free Technology and a research resource, making aggression and science the same strategy rather than a trade-off.
"Treasures of Nineveh" grants a free Technology upon capturing a Settlement for the first time, in its Antiquity Age Apex tier paired with a free Codex (a research-boosting resource) from that same capture — though Codices stop coming from Technologies once you have this ability, so conquest becomes your primary Codex source rather than a bonus on top of normal research.
The Magarru is a unique Chariot-replacement with increased Movement that can move after attacking while ignoring zone of control. The Turtanu is a unique Commander that grants +5 Combat Strength against Districts to Infantry and Cavalry units within its command radius — a strong pairing with siege equipment against fortified cities.
Assyria's unique buildings, the Royal Library and the Citadel, combine into the Ekallu Unique Quarter when built together, adding bonus Production for every Great Work present in that city. The associated Wonder, Dur-Sharrukin, acts as a Fortified District and adds Combat Strength to Fortified Districts empire-wide.