Harvest Moon: The Lost Valley is a single player game where you take on the role of a traveler who becomes a farmer to help the local spirits. The storyline of the game can be played through quickly or as slowly as you'd like, as the four seasons won't return until you've completed all of your tasks.
Time-wise, there are four seasons per year (Spring, Summer, Fall, and Winter), and each season is made up of 30 days. Most likely your first year is going to be a Winter scene, as that's the storyline of the game, but once you solve the excessive snow problem, the normal seasons will return.
The in-game time is faster than previous versions of the game series. Instead of the usual 10 real-time seconds to 10 in-game minutes, Lost Valley runs at a faster clock speed. It is closer to about 7 real-time seconds per 10 in-game minutes. That doesn't mean that you don't have time to do all of your chores. There's still plenty of time to go fishing, talk to villagers, and other activities. Time does not stop indoors.
You can save your game at any time by pressing the X Button and selecting Save/Load. The game has two save slots available, which you can select at any time. You aren't locked to using a specific save slot like in other versions of the game series.
Your character will have dreams that occur during the night. These dreams will give you gameplay tips, be messages from the Harvest Goddess, or hints about upcoming events such as birthdays or unlocking villager. You aren't guaranteed to see a dream every night, so don't worry if you don't experience one for a while.
There is a stamina meter in the upper-left corner that depletes as you use your tools, but it is very generous. With all of the activities I do in-game, I have yet to completely run out of stamina. There is also a face health meter that lets you know how healthy you are. The sadder the face, the more stamina you'll use when doing your chores. Stamina can be restored by eating food or going to bed.
Your main merchant friend, Sam, will be the one who sells you supplies and buys your farm products. There isn't a shipping bin in this version of Harvest Moon; just a shipping Sam. He is available every day in front of your house from 6:00 am to 8:00 pm. Sam's inventory items will increase as you proceed through the game. Alternatively, you can also sell items to Iris and Hanna when they are in shopkeeper mode in front of your house. Iris will pay more than Sam for flowers that you grow, and Hanna will pay more for crops and animal products. You can decide if you want to hoard all of your products until the other vendors are available or if you want to just sell them to Sam.
In the valley you can grow crops from any season while it is continuiously magical Winter (e.g., Strawberries in snowy Summer are okay), but once you return the seasons to the valley the crops will wilt when the season change as expected in a Harvest Moon game. For example, if you are still working through the main storyline to return the seasons, and you return Spring season early enough that the snow melts, when snowy Summer arrives your Spring crops will wilt. If you hadn't unlocked Spring to have the snow melt, and you reach Summer, the crops will continue to grow after the season change.
The friendship indicator in this version of Harvest Moon is called Chemistry, and you can easily find your chemistry relationship with the other villagers by checking your farmhouse bookshelf. You won't be tossing gifts at people to earn their trust; rather, you just have to interact with them as friends. The Chemistry level will naturally increase over time.
As you unlock the sleeping Harvest Sprites, you can ask them to help you with your chores. Their ability to do the chores will increase over time, so don't be concerened if you notice Dewey doesn't water all of your crop if you've just recently unlocked his ability. The farther you go in the game, the more sprites you can have assigned to chores at one time.
The Harvest Sprites will work between 8:00 am and will stop working at 6:00 pm, and this is important for the red sprite, Calvin. He is in charge of bringing your animals in and out of their barns when you ring the Grazing Bell on the barn's entrance. If you don't ring the Grazing Bell before Calvin stops work at 6pm, then your animals will be stuck outside overnight! This will increase their stress levels by about 2%, and a high stress level can result in grumpy and sick animals. Make sure you return your animals to their barns before 6pm.