1. Running- Get at least level 1 RUN (Running raises this skill level)
2. Jumping- Get at least level 1 JUMP (Jumping raises this skill level)
3. Healing- Get at least level 1 HEAL (Healing from damage taken raises this skill level)
4. Fortitude- Get at least level 1 FORTITUDE (Taking damage raises this skill level)
5. Collecting- Get at least level 1 COLLECT (Collecting gems raises this skill level)
6. Relationship- Get at least level 1 LOVE (Trading gems to the boy raises this skill level. This will also raise your amount of hearts)
7. Interaction- Get at least level 1 INTERACT (Talking to NPCs raises this skill level)
8. Sleeping- Get at least level 1 SLEEP (Ending the day raises this skill level)
9. Idle- Get at least level 1 IDLE (Doing nothing raises this skill level)
10. Knowledge- Get at least level 1 LEARN (Every 100 gems you collect raises this skill level)
11. Air Recovery- Perform an Air Recovery by tapping X while in the air after taking damage.
Entries #12-#17 show the skills and where to find them.
12. Double Jump- Get the DOUBLE JUMP skill (JOE can give you this skill for 100 gems, or you can get it from JOY for 50 gems after having an "air-time" of at least 2.6 seconds.)
13. Dash- Get the DASH skill (FINGERS can give you this skill for 150 gems, or you can get it from FLEET by completing his challenge in under one minute)
14. Regen- Get the REGEN skill (JOHN can give you this skill for 100 gems, or you can get it from MOMMA ROUNDITE for 50 gems by healing 15 damage in one go)
15. Hardiness- Get the HARDY skill (BRAINY can give you this skill for 150 gems, or you can get it from HULKER for 50 gems by getting hit 5 times without hitting the ground. You must use air recoveries to do this)
16. Radar- Get the RADAR skill (SQUARITE JUINOR can give you this skill for 150 gems, or you can get it from NAILS for 400 gems. Just stick with SQUARITE k? :P)
17. The Girl- You start with it.
Codex entries #18-#29 involve talking to certain NPCs.
18. The Boy- Talk to the boy at the beginning of the game.
19. Fleet- Roundite: in the caves under your house.
20. Joy- Roundite: in the storage area at the top of Earth Village.
21. Nails- Roundite: next to the Lava store in Earth Village.
22. Hulker- Roundite: bottom of Earth Village.
23. Momma- Roundite: next to the house in the west of Earth Village.
24. Joe- Squarian: entrance to Sky Village
25. Fingers- Squarian: near gem store room in Sky Village.
26. Gordon- Ghost Squarian: in the church
27. Brains- Fat Squarian: upper level (left) of Sky Village.
28. Junior- Tiny Squarian: upper level (right) of Sky Village.
29. Computer- Use the computer in Sacred Grounds, west of your house. (To get there, give 100 gems to get through the door or jump up through the bottom of the building. You'll need double jump + level 5 jump for this)
30. Mains Water Supply- The switch and machine like thingy in the room above the MAGMA CAVE.
Entries #31- #35 involve getting hit by certain monsters.
31. Oiler - Black oozie enemies. You can find them everywhere in darkened areas (Cave/Magma Cave/Mine,Tower)
32. Spiker - Spikey enemies you can find everywhere, there are some right by your house.
33. Big ol Wasp - Flying enemies you'll find pleanty in the Overground area.
34. Frisbee Worm - Found in the mines and above the roundite village.
35. Tyrant - Big black enemies that shoot fireballs. In the overground in the area under the church. You have to hit the Tyrant itself (not its projectiles) to get it added to the codex.
36. Shadow - Just go through at least one nightmare boss sequence.
37. My House - You start with it.
38. Overground - Climb to the open area above your house.
39. Tunnels - Climb to the underground area underneath your house.
40. Mine - Cave area on the East edge of the map. Enter from the overground tunnel next to the tower or the MAGMA CAVE or across from the TUNNELS themselves.
41. Magma Cave - Cave at the very bottom of the map, west end. Either climb down the Mine or go across from the Earth Village.
42. Giant Tree - North West corner of the map. Just climb up the tunnel from your house and head west and you'll run right into it.
43. The Tower - East end of the map. One of the trickier places to reach. When starting out the best thing to do is to climb the TREE, hop over the ledges to the CHURCH. Exit near the little grave at the edge and jump down to the lower overhang in the OVERGROUND so you can reach it.
44. Sky Village - Climb to about 3/4 of the way up the tower and it's right there (on the left).
45. Earth Village - South West corener of the map. Either climb all the way down the MAGMA CAVE and work your way west or get double jump and hop over the lip in the cave near your house under the big metal chute coming out of SACRED GROUNDS.
46. Church - North part of the map. Climb up the tree and across the branch sticking out and you can do a few jumps to the church from there.
47. Sacred Grounds - Slighty Northwest of the starting area.
48. Magical Gems - Collect a red gem.
49. Dark Gems - You need to beat the nightmare to get that.
50. Huge Gems - Collect a giant gem.
51. Postboxes - Touch a postbox. There is one right above your house.
52. Lava - You can find this plenty if you just head to the bottom right corner of the map.
53. Water Pump - Pull the lever in the little room above the MAGMA CAVE. You'll need double jump or Level 5 jump to reach it.
54. Lock - The door mechanism just outside SACRED GROUNDS, in the tunnel you can climb to get up to OVERGROUND.
55. Codex - Open the codex window.
56. Internet Awareness- Talk to BRAINS a lot to get this.
Get on a ledge then when it comes to slash double jump to the other ledge and wait for it to run. This way, you have a far better chance the rocks will come and hit it, then rush to where it was hit collect the gems and repeat. When it starts the wave thing of shooting to full arena beams in both directions stay on a ledge. Right before it launches them at you double jump to the center and fall then get back on a ledge and repeat this. That's about all there is too it :)
Did my GUIDE WRITING skill level up yet? >:D