"Druid damage buff applies to all units in the healing area as long as the druid has a target to heal. The damage bonus applies to undamaged units and allied units as long as they are in the healing area of effect."
"Units added in production queue that are not on the field of battle still take up population space."
"By default, holding alt and right clicking a group of units to a valid garrison-able target, will allow you to garrison them in it. You can hold shift and issue the garrison command and units will try to fill up the available garrison space in order."
"Destroying a building that is doing a research will cancel the research in it. For example in pvp if you snipe the town centre doing the age up tech, you can forcefully delay your opponents up time."
"You can cancel any research at any time and you will get full resource refund."
"If a building is destroyed for any reason, you will get resources back proportionally to how much time was left to finish said structure. For example destroying a 50 wood house that has been 60% done will refund the owner ONLY 20 wood."
"All hero units regenerate health and are resistant to conversion but are not immune to it."
"Enemies in legendary quests have bonus damage above the normal rates against most targets with the exception of siege, which makes battering rams particularly useful at soaking up damage."
"Auras do not stack. Having more than one norse chief for example, will not increase the health of units exponentially."
"Visiting other players city is disabled for now. Please stay tune for further updates."
"Sacred deers are herdable and not huntable. They also automatically convert to the player that has a unit nearby which means you can 'steal' them from your enemies if left unguarded."
"Age of empires is a lifestyle game. - Andreas Petrus Maximus the VIII" (it took longer than you think to find the latin origin of the name

)
"All norse military units have the same construction rate, however villagers will construct buildings faster."