What Is a Boss Fight in Video Games? A Simple Guide

If you have ever asked what is a boss fight in video games?, here is the plain answer: it is a battle against one enemy that is much stronger than the rest, usually at the end of a level or a stage of the game. It is a test of everything you have learned so far. This guide explains what makes a boss different, the parts most boss fights share, and then reads a real boss from the code of a free browser tank game, with a plan you can follow to beat it.

What is a boss fight in video games? The short answer

The common glossary of video game terms defines a boss as a powerful computer-controlled enemy "that is typically much more difficult to defeat compared to normal enemies, often at the end of a level or a game." A boss fight is the battle against it.

Normal enemies come in numbers and go down fast. A boss is one enemy that takes many hits, attacks in its own way, and often changes the rules of the space you are in. Beating it usually closes a chapter of the game.

What makes a boss different from normal enemies

Most bosses stand out in a few ways at once:

• Toughness. A boss has far more hit points than anything else you have met.
• A warning. The game tells you it is coming, with a message, a sound or new music.
• A health bar. You can see how much is left, so every hit feels like progress.
• Patterns. It attacks in set ways you can learn, instead of just running at you.
• A big finish. Its defeat gets more noise, light and reward than a normal kill.

Patterns and phases: how you learn a boss

A good boss is a puzzle as much as a fight. Its attacks repeat, so you can watch, spot the gaps and move into them. That is a pattern.

Many bosses also change when they are hurt. Past a certain point they speed up or add a new attack. Each of these stages is called a phase. A phase change keeps the fight fresh just when you thought you had it solved.

When you meet a new boss, try this order: survive first, watch what it does, then attack in the safe gaps. Do not trade hits with it until you know its pattern.

A worked example: the zero-day boss in Tank City Zero Day

Tank City Zero Day is the second game on the free Tank City Reboot site. You guard a CPU core inside a computer, wave after wave. Every fifth wave, a zero-day boss breaks through the walls, to its own chiptune soundtrack. Its card explains the real idea: a zero-day is a flaw nobody has patched yet, because the makers do not know it exists. Here is the boss as the game's code builds it.

The zero-day boss, phase by phase, from the game's code.

The warning

The wave card reads WARNING: ZERO-DAY DETECTED, and a warning sound plays. The boss arrives over 1.5 seconds and the screen shakes. On a boss wave it comes with one group of three botnet drones for every five waves played.

How tough it is

It takes 40 hits on wave 5, and 15 more on each later boss: 55 on wave 10, 70 on wave 15. A health bar runs across the top of the arena while it is in play.

Phase 1: above half health

The boss drifts on a looping path in the upper half of the arena. It is a 32 pixel box, twice as wide as your tank, and it breaks every wall it passes through. Touching it counts as a hit on you. Every 1.3 seconds it fires three shots in a spread, aimed at you.

Phase 2: half health or less

Once half its health is gone, it changes. The spread now comes every 1.1 seconds. Every 2 seconds it also fires a ring of 12 shots in all directions. Every 7 seconds it calls two more botnet drones through a gate.

The finish

Destroying it scores 2500 points, times your chain multiplier. The game freezes for 0.3 seconds, its longest hit stop, and the screen shakes harder than at any other moment in the game.

A plan for beating the zero-day boss

Turn those rules into steps:

1. Clear the drones first. They come in threes and hunt you, so they are the real danger early on.
2. Keep your distance. The boss breaks walls, so cover near it will not last, and touching it costs you.
3. Read the spread. Three shots fan out from the boss toward you. Move sideways, across the fan, between volleys.
4. Get ready for the change. When its health bar reaches the halfway mark, the rings start. Find open space before you push it past half.
5. Use your tools. You cannot be hit mid-dash, so a dash can carry you through a ring. The Sandbox upgrade gives a shield that stops one hit and recharges.
6. Save your chain for the end. The boss is worth 2500 times your chain, which can reach x8, so killing a few drones just before the last hit pays.

Upgrades you pick after each wave make each boss easier to answer. The boss grows by 15 hits each time; your volley and fire rate can grow too.

Why the boss comes every fifth wave

A boss works best as a checkpoint for skill. Four normal waves teach you the threats and let you collect upgrades; the fifth asks you to use all of it at once. Then the next wave is a normal one again, and the climb toward the next boss starts over. If you like reading games this way, the same idea of rising challenge runs through this guide to difficulty curves.

Frequently asked questions

Is the zero-day boss the same every time?

Its attacks are the same each time, but it gets tougher: 15 more hits for every boss after the first. Your upgrades grow between bosses too.

Why do bosses have health bars?

A boss takes many hits, so a bar shows you are making progress. In Zero Day the bar runs across the top of the arena while the boss is in play.

How many hits does the zero-day boss take?

40 on wave 5, then 15 more on each later boss: 55 on wave 10 and 70 on wave 15.

Does the first Tank City game have a boss?

No. The first game's stages each send 20 malware tanks, ending with stage 6, KERNEL, which has the most armored rootkits. The boss is a Zero Day feature.

Get started

Reach wave 5 in Zero Day and try the plan above. Watch for the warning, read the spread, and be ready when the health bar hits half.

Play Tank City Reboot: it is free, plays in your browser on a computer or a phone, and needs no account.