Consider: Ngao Mbeba. Costs 20 more production than normal swordsmen. However, more mobile (moves through forests without penalty- perfect for Kongo's rainforest starts). And +10 defense vs ranged fire. Most importantly: resourceless. Highest city defenses in classical era: 40. Ngao Mbeba with Oligarchy has 39. I.e. they can handle Classical era cities with no trouble. In the past, the Mbeba was considered the weakest of the swords UU. But now with the resource restrictions, and the nerfs to city defense, they're arguably the best of the Swords UUs as you can spam them out and upgrade into them. The usual counter to swordsmen are other swordsmen or archers or city defenses. But the AI isn't going to build lots of swords due to resource issues and archers do nothing to the Ngao and city defenses have been nerfed. Even without a GG they'll crush any nearby civs. With a GG and they'll massacre everything. At 2 promotions, and a GG they'll have 4 moves, 44 strength (64 defense vs Xbow fire), and the ability to walk through forests without penalty. In other words, Kongo now arguably has one of the top 5 UUs in the game. Kongo Build Order: Skip AH and archery and slingers entirely. Use warriors for defense. Try to get 2 of them promoted to level 1. Try to kill 3 barbs. Get second city at some point (for more chops). Since you start in the rainforest anyways, beeline Iron Working. Then IW. Save money. Moment you get Iron Working, upgrade 2 warriors to Ngao. Chop out 2-3 more. 4-5 Ngao can massacre everything in the ancient era. Get an encampment or two. Get GG by time you get Oligarchy in the Classical era. continue domination.