Here is the full list of all 39 Yrminsul achievements.
Thanks for playing through Yrminsul!
Kill 10000 foes
You've conquered 30 islands
Grab the Seed of Life
Claw the Seed of Peace
Hoard 2000 Infamy
Collect 15000 infamy
600 days of conquest
Take the Seed of Health
Acquire the Seed of Plenty
All towers unlocked
Complete the Famine tree
All powers unlocked
Complete the Plague tree
Complete the War tree
Collect 10000 infamy
Kill 5000 foes
Complete the Death tree
200 towers on map
You've conquered 20 islands
450 days of conquest
Collect 6000 infamy
300 days of conquest
Hoard 1000 Infamy
100 towers on map
7 Powers unlocked
6 towers unlocked
150 days of conquest
Collect 2500 infamy
Kill 1000 foes
You've conquered 10 islands
50 towers on map
50 days of conquest
Kill 500 foes
25 towers on map
Hoard 300 Infamy
Collect 1000 infamy
Kill 100 foes
350 towers on map