Here is the full list of all 14 Realm Grinder achievements. It takes around 200 hours to unlock all of the achievements on Windows.
Unlock the Automatic Casting upgrade.
Gain 1 Gem.
Produce 10.000 mana in a single game.
Build 100 buildings in a single game.
Find 50 Faction Coins in a single game.
Click 100 times in a single game.
Gain 1.000 Coins in a single game.
Find 10 Artifacts.
Unlock Archeology.
Have 500 Assistants.
Unlock the Dragons.
Unlock the Mercenaries.
Reincarnate once.
Cast 500 spells in a single game.