Here is the full list of all 15 Mushroom Wars achievements.
Capture an enemy building without having any of your own
Encounter forest warriors in Campaign
Encounter aliens in Campaign
Complete Campaign
Complete Campaign on highest difficulty
Complete Campaign in under 60 minutes.
Earn each reward at least once
Earn all 9 rewards in a single Campaign level
Earn all rewards in all Campaign levels
Win a Skirmish game
Achieve victory on all Skirmish maps on highest difficulty
Upgrade your village to level 5
Achieve level 5 morale
Capture 300 enemy buildings
Achieve maximum attack level