Easy "Bad day" Achievement...
	Easy "Total crafter" Achieveme...
	Various Steam Achievements...

Giant mites drop out of trees occasionally when a dwarf starts cutting it down. Even on the highest difficulty setting, a giant mite is no thread for even an unarmed dwarf. Your best chance is to do it on the forest world right in the beginning (campaign or free game). Manually control a dwarf without any armor on and cut trees down until a mite spawns. Stay in manual control and simply do nothing until the mite killed your dwarf.

A way to check what you haven't crafted is in the technology tree page (Icons on the right side of the screen) all the craftable items are listed under their tech, the ones you haven't crafted have a darker color background (crafted recipes appear to have a near white background).

Complete the indicated task to unlock the achievement.

Achievement	How to unlock
Alpha Dwarf	Win 20 PvP multiplayer battles.
Armageddon	Reach for 5 simultaneously open monsters portals.
Bad day	Giant mite killed a dwarf.
Blameless	Avoid of damage main stockpile during multiplayer game.
Blood lust	Kill 10 monsters in 2 seconds.
Bookworm	Read 100 books.
Bra-a-a-ins!	Collect 100 zombie's brains.
Burst of greed	Bring back from biome at least 1000 resources.
Castle Defender	Help to defend dwarves' shelter during 12 hours in multiplayer game.
Chicken exterminator	Kill 10 chickens.
Collector	Collect maximum amount of resources for multiplayer victory.
Collector	Collect 999 resources.
Creator of the public world	Create multiplayer server.
Disinsector	Destroy 10 nests of giant ants at one level.
Don't even try to shout!	Kill 10 banshee.
Dungeon Keeper	Complete 4th level of campaign.
Dwarfgineer	Build up portal at your own server.
Epic defeat!	Lost multiplayer battle.
Even alone is a warrior!	One dwarf killed 100 foes.
Flying assistants	Cast imps.
Foreman	Improve all dwarf's skills.
Fortress Defender	Help to defend dwarves' shelter during 3 hours in multiplayer game.
Free Builders	Play 5 hours in Creative mode.
Get strong together	Win 10 cooperative multiplayer battles.
Get your own skeleton in the cupboard	Collect 100 bones.
Goblinator	Kill 10 Goblins.
God Hand	Kill 100 monsters with your spells.
Gourmet	Cook all dishes.
Great Explorer	Win 50 battles at biomes.
Great World Keeper	Keep server online during 12 hours.
Hardcore man	Reach 12 level in hardcore mode.
Hird of Dwarves	Level up one of the battle skills for 5 dwarves to maximum in multiplayer game.
I am a pharaoh	Build shelter inside a pyramid.
Invulnerable	All dwarves should survive at a level.
Land holder	Complete 1st level of campaign.
Liberator	Free 20 yetis from captivity.
Long way begin	Craft 1st item.
Long-playing	Above 100 hours in the game.
Major Defender	Inflict maximum amount of damage to monsters for victory.
Major Supplier	Share 1000 resources with other players.
Manufacturer	Build 10 machine-tools for items crafting at one level.
Megacrafter	Craft 200 items at a time.
Mercenaries exploiter	Use at least 50 mercenaries during 1 battle at the biome.
Military Engineer	Build up portal at your own server at high level of difficulty.
Military Researcher	Open all technologies during one session in survival mode.
More snails!	Convert 50 monsters into snails.
Multidwarf	Play 10 multiplayer battles.
Naturalist	Investigate all creatures.
Oktoberfest	Give beer to all dwarves.
Overboost	Grab at least a half boost rooms at the biome.
Overpopulation	Create server with maximum number of active players.
Palace	Build shelter with 100% comfort.
Persistence	Break 10 pyramid's blocks.
Professional Miner	Extract all minerals at one level.
Railwayman	Build a railway 100 blocks long.
Reviver	Revive a dwarf from soul keeper.
Sand master	Complete 3rd level of campaign.
Sapper	Use Magic Explosion spell 10 times.
Shopping	Spend 200 gold coins.
Sinbad the pedestrian	One dwarf passed 1000 blocks.
Sliders	Travel to any biome.
Supplier	Share resources with other players.
Survival	Survive in monsters wave.
The worst that could happen	Kill 10 giant skeletons.
Thief	Steal at least 100 items during 1 battle at the biome.
Tomb rider	Break the pyramid's sarcophagi.
Total annihilation	Kill 50 Goblins.
Total crafter	Craft all tech tree recipes.
True dwarf!	Collect 200 gold ore.
Underground king	Reach 14 level.
Who needs elves!	Archers killed 100 foes.
Winter master	Complete 2nd level of campaign.
World Keeper	Keep server online during 3 hours.
Worm hunter	Kill giant worm.
You've been digested!	Your dwarf have died inside the Crookshanks.