Here is the full list of all 29 Dwarfs - there are F2P achievements.
Survive a 60-minute Arcade Game on Normal Mode
Open 2000 Caves in Arcade Mode
Get awarded with Two Axes on every single Challenge
Miss with every axe in the Carnival minigame
Hit only zombies, and at least five of them, in the Carnival minigame
Hit only poles with all axes in the Carnival minigame
Get a score over 500 000 in Normal Arcade Mode!
You've slain 30 Bosses
Have 10 Outposts with Taverns in Arcade Mode
Get a cumulative total of 40k gold
Use Instant Seal on 10 Water- or Lava Caves!
Dig through a total of 25000 squares in Arcade Mode.
Dig through a total of 1000 mineral squares in Arcade Mode.
Get a score over 500 000 in Easy Arcade Mode!
Get a score over 500 000 in Hard Arcade Mode!
Get a score over 500 000 in Tedi Hardcore Arcade Mode!
Manage to die in an arcade game in less than fifteen seconds!
Have 25000 gold coins in Arcade Mode!
Level a Digger Dwarf to Level 15!
Level a Warrior Dwarf to Level 15!
Kill a Goblin by luring him down a hole
Have 25 Warriors at the same time in Arcade Mode
Have 2500 Diggers in all games total
Play the Carnival minigame
Hit only elves, and at least five of them, in the Carnival minigame
Hit a target with every single axe in the Carnival minigame
Score at least 500 points in the Carnival minigame
Score at least 1000 points in the Carnival minigame
Score at least 2500 points in the Carnival minigame