First things first
A/D = Move left or right
Spacebar = Jump
The Spawn Point
When you start Terraria, you spawn in a randomly generated map. Where you spawn can determine what your tactics will be.If you spawn on flat ground, chances are you will be surrounded by many tall trees . You can get alot of wood this way, and is the best place to spawn . Your first house should be above ground.
If you spawn in a hole or at the side of a hill, you should make your first house underground or in the side of the hill. It may not look as good as a house above ground but it is safer than one.
If you spawn on uneven ground, the first thing you should do is flatten the area as much as possible. Trees may be hard to find and you may have to walk before you find some. Your first house should be on the flattened area, ideally made with stone if you do not have enough wood.
The house should be secure, without any holes for enemies to come in through. The house will function primally as your main Crafting station, and your spawn point should be in your house so that you do not have to risk dying should you have to respawn during a blood moon or Goblin invasion.
Note: This is just a guide, and you do not have to follow it exactly. Feel free to explore new ways of doing things!
Health and Mana
You may notice your health represented by small red hearts at the top right, but you will have no mana until you obtain a Mana crystal , crafted from ten fallen stars. These stars drop at night at random places in the map and are easy to find. Health crystals can be found in caves and picked up with a hammer , and increase your max health .
After building your first house and surviving the night, choose a direction to travel in. Remember to bring some torches with you! Torches are crafted with gel and wood and light up the area around you, and can be placed. Chop down as many trees as possible on the way, as wooden platforms, crafted from wood , make escaping from deep caves easy.
You may notice some ore under ground or even above ground when you are walking. Ores are used to craft bars at a furnace , and those bars are used to make equipment like armour, tools and weapons, so remember to dig them up! Caves usually contain alot of ore, so remember to explore caves when you encounter them.
However, without proper equipment, refrain from travelling too deep underground as you may accidentally fall and get killed. Stronger enemies such as the skeleton spawn deep underground, and the deeper you go, the harder it is to get back up.
You may encounter some chests on your way, and they may contain some useful items, and are the main reason you should explore the caves. Items like the Cloud in a bottle can help you in your adventure alot. The chests can also contain bars to help you craft more items .
The danger of travelling
Sometimes when you are travelling, the sky may turn a unsual colour. This means that you are approaching a new biome.
Green = Jungle
Yellow = Corruption
As this is simply a beginner's guide, I'm not going to elaborate on what they are about, other than that they are very dangerous and you should stay out of them until you get at least silver armour.
Digging down will let you explore more caves, but again, beware that you dont travel to far down.
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