I played a 4v4, as the Malians. Usually, I stick to my own town, and defend its multi-layered walls, with archers. However, I was feeling really safe, and decided to send my army into my ally's town, and ward off the enemy eagle warriors! It worked! Finally!
Enemy battering rams were smashing down the houses, but I sent cavalry, to beat up the rams! Then, I sent my villagers to build defensive towers, in my ally's town. I made my infantry join the allies, and charge into the enemies, while my monks were healing my ally's wounded soldiers. I donated lots of lumber and food to them, and set up trebuchets, to knock down the enemy's pesky castles.
Soon, we stormed the enemy towns, and won the game. Wow! Offense, outside of attrition and counterattacks, I usually don't play offense, but I am a great team player, so I decided to help my allies make the comeback. They might've been AI allies, but I still felt helpful.
Although I'm anxious to return to PvP play, I'm sure my generosity will find its place elsewhere. If I do play a match, with an allied human, I'll probably say, "Hey, you can have my sheep and I'll send some Spearmen to guard your town against enemy horsemen." Giving away sheep sounds far too generous, but it's a nice thing to do.