+ Estimated achievement difficulty: 4/10
+ Offline: 41 (1000)
+ Online: 0 (0)
+ Estimated time for 1000: 50-70 hours
+ Minimum playthroughs: 1 full, 2 half, and 1 quick 'beat the final boss' run.
+ Missable achievements: The Sheep Whisperer, Lightspeed Fighter, Legendary Gardener, Boss 'Time Limit' Achievements
+ Glitched achievements: None
+ Cheats disable achievements: No cheats
+ Difficulty affect achievements: Nope!
+ Unobtainable achievements: 0
+ Extra equipment needed?: None
Read the Ending Guide before attempting Ending B to have a general understanding of what will be required to get all endings, and to save yourself the most amount of time.
*General Warning* - Viewing Ending D will ERASE ALL of your saved games. This makes many more achievement's technically 'miss-able', but if you follow my instructions (in the Ending Guide), there is a way to prevent this from hindering your achievement progress. Consider yourself warned!
Breakdown:
Ending A: Plan to beat the game in less than 15 hours to earn Lightspeed Fighter. It is recommended that you play on the Normal difficulty (game allows you to change difficulty at any point) or lower to accomplish this. To give you a general idea, I was able to beat the game in a speed run in 7 hours and 30 minutes, which included skipping all text and cut-scenes (and I knew exactly what I was doing). Since its the first time you are playing the game, enjoy the story, but complete a minimal amount of quests and always follow where the red x is telling you to go next. However, to enable gardening and more efficient gardening, you must complete 2 specific quests, so do quests "Shopping List" and "A Return to Shopping" given from the Village's florist ASAP because they can be missed later in the story! If you follow these steps and play on Easy/Normal, you shouldn't have a hard time making 15 hours. At some point in the first 5 hours of the game (because after a certain event, sheep will no longer be found) - save your game and get The Sheep Whisperer. Then load your game directly after it unlocks to ensure you keep a low playtime. At the end of this run, you should have grabbed Call Her Back, Material Hunter, All Aboarded!, and all of the story related achievements.
Ending B: Relax, take your time on this run. Start looking to complete your weapon collection, but don't worry if you missed anything. Explore dungeons, and break every box you come across. Complete at least 30 quests to receive Village Handyman, Jack of All Trades, and Go-To Guy and start earning enough money to get upgrades and buy other quest items. Complete the fishing quests and earn Fish of Legend and A Round by the Pond. Completing this run gets you Lingering Memories.
Ending C: This time you will need to make sure you have 100% weapons (use the Weapons FAQ), earning you Weapons Collector. You can choose to attempt Man of Means, and get 1 million gold BEFORE you buy the remaining weapons, as they cost around 200K. If you haven't gotten Combo Fanatic and Combo Master by now, you should be strong enough to use my second method to get it. You should also be strong enough to plow through all bosses to earn every 'Time Limit' Boss achievement. Completing this run earns you Thank You.
Ending D: During this run, you should focus on earning Wordsmith. Completing this run gets you Something Very Special. Again...be prepared with a 'backup' plan (pun intended) before letting the game delete all your saves.
Cleanup:
First, tackle the Legendary Gardener achievement. Next, complete many quests and start upgrading every weapon for the three weapon upgrade achievements (these will probably be the last things you get, and are the most time consuming, use this guide for help). Last but not least, if you haven't gotten Man of Means by now, decide if you will earn money via harvesting (recommended), fishing, Junk Heap runs, or remaining quests. Completing all quests should net you around 500K, so you will still need to grind for money. Good luck (you'll need it)!