Terraria is a fairly easy game to play, but it's a difficult one to master. All these good techniques are elementary ones that most good players should have under their belt.
Enemies are handled very well with a piercing weapon when they're all in a line. This way, a player can shoot once and destroy all of them. This comes in handy especially when there are lots of enemies.
What to do:
- Face enemies on level ground, such as a hellbridge or Dungeon corridor.
- Use a weapon (i.e. the Vilethorn) that can move through walls. This makes it so much easier to pierce a group of enemies that have clustered in the wrong spot because of their AI leading them to you. (Angry Bones and other Dungeon Skeletons in particular).
- Keep attacking until all the monsters are dead. The advantage of attacking a group is that they can all be destroyed at once. Even a spear such as the Dark Lance can do this kind of thing.
Named for its technique in the game Team Fortress 2, this is a quick sweep of any ranged weapon in a circle around the user. It can be used to reveal and destroy any hidden enemies, or those too small and fast to be caught in another weapon's single-projectile hit. AoE weapons are best for this. It's designed to conserve mana or ammo and also kill the enemies easily.
What to do:
- Spy-checking is only possible with a weapon that fires multiple projectiles, or better yet, a wave of them. A very fast attack speed can also come in handy. Use a weapon such as the Aqua Scepter for this (in fact, it's the prime candidate, having a high mana cost as well).
- Weapons that fire bouncing bursts can also be used: the Water Bolt, Cursed Flames and Flower of Fire are all popular.
- Do your best to fire around walls too. This is where bouncing weapons come in handy; Crystal Storm is king.
- Always take your time when sweeping. It might take a little bit of experience to know how long you can shoot for without running out of ammo or mana, but it's better to do it this way so you can kill everything.
- It's also possible to make bouncing weapons bounce along a straight path to kill everything between two walls.
- If using a fast-firing weapon such as the Minishark or Megashark, try Meteor Shot. It bounces off walls, making it easier to hit more enemies. You will, however, need more shots, as these weapons have small projectiles.
Combat building is exactly what it sounds like: building a structure in combat to aid in your defense. While it may not be intricate, ten blocks of dirt can protect you pretty well from most enemies.
The main disadvantage of combat building is that it leaves you (mostly) useless in combat. Counter this with a small "attack hole" (two blocks is good) for you to shoot out of. Melee weapons, unless they are flails, are useless.
What to do:
- Never use combat building against an enemy such as Tim or the Dark Caster. Their projectiles can go through walls; at best, not keeping you safe; at worst, giving Tim a free shot at killing you.
- If you're surrounded by projectile-shooting enemies, take a Vilethorn. It shoots through walls, where an arrow slit in your building could allow projectiles to go both ways.
- If you're using an arrow slot, a bouncing weapon such as the Water Bolt or a gun equipped with Meteor Shot can be very useful to shoot enemies around walls.