Zhao Yun (in Dynasty Warriors 4)
Weapon: Fierce Dragon (Lv 10)
Power: +55
Stage: Battle of Bo Wan Po
Requirements: Lead Xiahou Dun to the ambush location on the middle path indicated (fire attack), then defeat him. Lure Han Hao to the ambush location on the top path indicated (Guan Ping ambush), and then defeat him. Lead Yu Jin to the ambush location on the upper bridge indicated (Guan Yu ambush), and then defeat him. Zhang Fei should raid the supply depot in an event. When Zhuge Liang meets Cao Cao a cut scene should occur.
Tip: If Zhuge Liang does not enter the castle you can use a horse to push him inside by moving sideways. Alternately, you can lead Cao Cao to Zhuge Liang.

Zhao Yun (in Dynasty Warriors 4: Xtreme Legends)
Weapon: Fierce Dragon (Lv 10)
Attack: +55
Method: Defeat Cao Ren, Xu Huang, Cheng Yu, Xu Chu, and Xiahou Yuan in under 5 minutes. Learned Fierce Dragons message.

Weapon: Raging Dragon (Lv 11)
Added Items: Dragon Amulet (Musou Gage) Lv18, Cavalry Armor (Ride Defense) Lv14, Elixir (Musou Gage Increase) Lv20, Herbal Remedy (Charge Attack) Lv13
Method: Find the decorated wooden box containing Ah Do (random) in under 2 minutes. Defeat all enemy generals. Achieve 200 KO Count. Zhao Yun and Liu Bei both reach the bottom right Chang Ban Bridge. All in under 13 minutes 30 seconds. Learned Lv11 weapon message.

Guan Yu (in Dynasty Warriors 4)
Weapon: Blue Moon Dragon (Lv 10)
Power: +57
Stage: Battle of Fan Castle
Requirements: Do not defeat Lu Meng, Lu Xun, or Zhou Tai until Guan Yu says "Curses! We've been surrounded!" All Shu officers that can defeat must defeat.

Guan Yu (in Dynasty Warriors 4: Xtreme Legends)
Weapon: Blue Moon Dragon (Lv 10)
Attack: +57
Method: Achieve 150 KO Count before the horse carriage crosses the center water path (approximately 4 minutes into stage). Learned Blue Moon Dragon message.

Weapon: Divine Dragon (Lv 11)
Added Items: Peacock Urn (HP) Lv17, Speed Scroll (Speed) Lv17, Huang Zhong's Bow (Arrow Attack) Lv13, Horned Helmet (Ride Attack) Lv20
Method: Keep damage to the horse carriage to a minimum. Defeat Yu Jin. Defeat Yue Jin. Defeat Li Dian. Achieve 200 KO Count. Learned Lv11 weapon message.

Zhang Fei (in Dynasty Warriors 4)
Weapon: Viper Blade (Lv 10)
Power: +58
Stage: Battle of Chang Ban
Requirements: Defeat Xiahou Dun, Xiahou Yuan, Xiahou En, and Xiahou De. Go to the Chang Ban Bridge to trigger the Zhang Fei yell event, then rescue Liu Chan by getting him while mounted on a horse.

Zhang Fei (in Dynasty Warriors 4: Xtreme Legends)
Weapon: Viper Blade (Lv 10)
Attack: +58
Method: Do not let more than 1 team of enemies pass through the Chang Ban Bridge. Defeat all enemy generals that come to the Chang Ban Bridge (Xiahou Dun, Xiahou Yuan, Yu Jin, Zhang He, Cao Ren, Li Dian, Xu Huang, Yue Jin, Xu Chu). Learned Viper Blade message.

Weapon: Venom (Lv 11)
Added Items: Tiger Amulet (Attack) Lv20, Horned Helmet (Ride Attack) Lv13, Elixir (Musou Gage Increase) Lv18, Herbal Remedy (Charge Attack) Lv17
Method: Do not let any enemies pass through the Chang Ban Bridge. Defeat all enemy generals that come to the Chang Ban Bridge. Defeat Cao Cao when he comes to the Chang Ban Bridge. Learned Lv11 weapon message.

Liu Bei (in Dynasty Warriors 4)
Weapon: Gold Moon Dragon (Lv 10)
Power: +52
Stage: Battle of Ru Nan
Requirements: Defeat Xiahou Yuan within the first 3 minutes of the stage. Join with Zhao Yun, Zhang Fei, and Guan Yu in that order. Defeat all of Cao Cao's other officers before reinforcements arrive.
Tip: Li Dan must be defeated after meeting Zhao Yun. Xiahou Yuan must be defeated before Guan Yu appears. The other generals can be defeated in any order.

Liu Bei (in Dynasty Warriors 4: Xtreme Legends)
Weapon: Gold Moon Dragon (Lv 10)
Attack: +52
Method: Defeat all 5 enemy generals in under 4 minutes. Without defeating more than 15 enemy soldiers. Learned Gold Moon Dragon message.

Weapon: King of Shu (Lv 11)
Added Items: Tortoise Amulet (Defense) Lv19, Speed Scroll (Speed) Lv14, Horned Helmet (Ride Attack) Lv9, Seven Star Sash (Luck) Lv20
Method: Defeat all enemy generals. Do not allow enemy generals to retreat and return to the battlefield for more than 4 times. Avoid the Liu Bei killing innocent soldiers cutscene by not killing enemy soldiers. All in under 10 minutes. Learned Lv11 weapon message.

Zhuge Liang (in Dynasty Warriors 4)
Weapon: Peacock Feather (Lv 10)
Power: +50
Stage: Battle of Wu Zhang Plains (Musou Mode only)
Requirements: Select Battle of Jie Ting first, then Battle of Wu Zhang Plains. Go to Zhang He and an event should occur. Defeat Zhang He and approach the Wei fortress until the taunt event occurs. When the supply troop appears defeat Xiahou Dun. The supply troop should reach the Shu camp.
Tip: If the Battle of Jie Ting is not selected first, there will be no supply troop at Wu Zhang Plains.

Zhuge Liang (in Dynasty Warriors 4: Xtreme Legends)
Weapon: Peacock Feather (Lv 10)
Attack: +50
Method: Defeat Yue Ying 6 times, each time very quickly thus receiving a "Quick Victory" comment. Learned Peacock Feather message.

Weapon: Divine Feather (Lv 11)
Added Items: Tiger Amulet (Attack) Lv11, Nanman Armor (Arrow Defense) Lv20, Cavalry Armor (Ride Defense) Lv20, Seven Star Sash (Luck) Lv9
Method: Defeat Yue Ying 6 times, each time very quickly thus receiving a "Quick Victory" comment. Defeat Ma Dai. Defeat Fa Zheng. Defeat Yan Yan. Learned Lv11 weapon message.

Pang Tong (in Dynasty Warriors 4)
Weapon: Tornado Staff (Lv 10)
Power: +51
Stage: Battle of Luo Castle
Requirements: Defeat all generals east of the castle. When Zhang Ren attacks refuse his duel and lead him across the bridge south of the castle and fight him until the bridge event. When the bridge is destroyed defeat Zhang Ren.

Pang Tong (in Dynasty Warriors 4: Xtreme Legends)
Weapon: Tornado Staff (Lv 10)
Attack: +51
Method: Achieve 100 KO Count in under 3 minutes. Learned Tornado Staff message.

Weapon: Great Phoenix (Lv 11)
Added Items: Dragon Amulet (Musou Gage) Lv14, Nanman Armor (Arrow Defense) Lv20, Cavalry Armor (Ride Defense) Lv20, Seven Star Sash (Luck) Lv7
Method: Succeed in all of Pang Tong's battle strategies. Without defeating any of the enemy bomb tossing soldiers. Achieve 450 KO Count. Learned Lv11 weapon message.

Huang Zhong (in Dynasty Warriors 4)
Weapon: Oracle Sword (Lv 10)
Power: +54
Stage: Battle of Jian Ye
Requirements: Defeat Sun Ce, Sun Quan, and Sun Shang Xiang at least once
before they become commanding officers.

Huang Zhong (in Dynasty Warriors 4: Xtreme Legends)
Weapon: Oracle Sword (Lv 10)
Attack: +54
Method: Achieve 100 KO Count in under 6:35 minutes.Learned Oracle Sword message.

Weapon: Venerable Master (Lv 11)
Added Items: Peacock Urn (HP) Lv8, Huang Zhong's Bow (Arrow Attack) Lv20, Nanman Armor (Arrow Defense) Lv20, Herbal Remedy (Charge Attack) Lv16
Method 1: Shoot Guan Yu off his horse before he challenges at the castle wall (approximately 30 seconds into stage). Defeat Zhou Cang. Defeat Guan Ping. Defeat Zhao Yun. Defeat Zhang Fei. Achieve 100 KO Count. Learned Lv11 weapon message.
Method 2: Shoot Guan Yu off his horse before he challenges at the castle wall (approximately 30 seconds into stage). Defeat 3 of Zhou Cang, Guan Ping, Zhao Yun, and Zhang Fei. Achieve 200 KO Count. Learned Lv11 weapon message.

Wei Yan (in Dynasty Warriors 4)
Weapon: Comet Strike (Lv 10)
Power: +57
Stage: The Campaign for Jing
Requirements: Defeat Han Xuan before the enemy reinforcements appear.

Wei Yan (in Dynasty Warriors 4: Xtreme Legends)
Weapon: Comet Strike (Lv 10)
Attack: +57
Method: Achieve 50 KO Count in under 4 minutes. Learned Comet Strike message.

Weapon: Meteor Strike (Lv 11)
Added Items: Peacock Urn (HP) Lv18, Nanman Armor (Arrow Defense) Lv14, Cavalry Armor (Ride Defense) Lv16, Herbal Remedy (Charge Attack) Lv19
Method 1: Defeat Xiahou Wei. Defeat Xiahou Hui. Defeat Xiahou He. In any order. All before Zhuge Liang orders the all out attack on Wei Yan (approximately 2:30 into stage). Learned Lv11 weapon message.
Method 2: Defeat Xiahou Wei. Defeat Xiahou Hui. Defeat Xiahou He. In any order. After Zhuge Liang orders the all out attack on Wei Yan (approximately 2:30 into stage). Defeat all Shu generals and sub-general as they appear (Ma Dai, Guan Xing, Wang Ping, Zhang Bao, Jiang Wei). Encounter Zhuge Liang. Achieve 200 KO Count. Learned Lv11 weapon message.

Yue Ying (in Dynasty Warriors 4)
Weapon: Oblivion (Lv 10)
Power: +53
Stage: The Nanman Campaign
Requirements: Defeat Zhu Rong in a duel. Trigger the fire attack against Wu Tugu. Ahui Nan and Dong Tu Ne must defect. Meng Huo must be defeated seven times.
Tip: Zhuge Liang will be in danger throughout the stage. Leaving your elite bodyguards near him (using the wait command) will improve his chances for survival. Increasing his morale by defeating enemies will also help. Having Ahui Nan and Dong Tu Ne defect may be another requirement for this weapon.

Yue Ying (in Dynasty Warriors 4: Xtreme Legends)
Weapon: Oblivion (Lv 10)
Attack: +53
Method: Defeat Zhang Fei. Defeat Huang Zhong. Defeat Ma Chao. Without losing any Tiger Tanks. Learned Oblivion message.

Weapon: Nether Realm (Lv 11)
Added Items: Tiger Amulet (Attack) Lv18, Huang Zhong's Bow (Arrow Attack) Lv13, Horned Helmet (Ride Attack) Lv14, Herbal Remedy (Charge Attack) Lv18
Method: Defeat the Five Tiger Generals (Guan Yu, Zhang Fei, Zhao Yun, Huang Zhong, Ma Chao). Keep all or most Tiger Tanks safe. Learned Lv11 weapon message.

Ma Chao (in Dynasty Warriors 4)
Weapon: Stallion Fury (Lv 10)
Power: +57
Stage: Campaign for Cheng Du (Musou Mode only)
Requirements: Defeat Pang De and Ma Dai. Ma Dai must be defeated only when he attacks the main camp.

Ma Chao (in Dynasty Warriors 4: Xtreme Legends)
Weapon: Stallion Fury (Lv 10)
Attack: +57
Method: Achieve 300 KO Count in under 5 minutes. Learned Stallion Fury message.

Weapon: Last Stallion (Lv 11)
Added Items: Tiger Amulet (Attack) Lv12, Horned Helmet (Ride Attack) Lv20, Cavalry Armor (Ride Defense) Lv20, Elixir (Musou Gage Increase) Lv15
Method: Achieve at least 500 KO Count. Receive Ma Chao is taking the lead message over 5 times. Finish the stage achieving twice the KO Count as the ally general in the second place. Learned Lv11 weapon message.

Jiang Wei (in Dynasty Warriors 4)
Weapon: Blink (Lv 10)
Power: +55
Stage: Battle of Tian Shui (Musou Mode only)
Note: This one wasn't it the Tips & Tricks article so it's still not confirmed.
Requirements: Defeat Cao Ren and Wang Lang in the north castle. Defeat the remaining generals outside, then defeat Yin Shang and Liang Xu in the east castle.
Tip: Enter all four gates of the two castles from the outside. You will need to trigger all the ambushes. Leave your bodyguards with Zhuge Liang to increase his odds of survival.

Jiang Wei (in Dynasty Warriors 4: Xtreme Legends)
Weapon: Blink (Lv 10)
Attack: +55
Method: Defeat Cao Ren. Defeat Zhang He. Defeat Xu Chu. Defeat Xu Huang. Learned Blink message.

Weapon: Prodigal (Lv 11)
Added Items: Peacock Urn (HP) Lv14, Wing Boots (Jump) Lv20, Horned Helmet (Ride Attack) Lv14, Herbal Remedy (Charge Attack) Lv17
Method: Defeat all 4 playable enemy generals plus 1 of the 2 generic enemy generals. Keep eliminating Liu Shan's destination enemy entry points to stop him from retreating for 8~9 minutes. All the while keeping Liu Shan's HP at approximately more than half. Learned Lv11 weapon message.