Mod Tester's Handbook tutorial - Crispy

Bug hunter

Tips for finding and producing bugs
Here are some methods you can adopt to find bugs in your game:

Be a loser
Fail challenges. Get yourself killed. Give up midway through a fight or a scripted sequence. Reload the game. Do you lose a life? What happens if you lose all your lives? Is the game saving properly? When you reload are you in the right place, with all the equipment you had before? Are all the NPCs where they should be? Is your mission progression saved?

Be fast
Find the quickest way to complete the game and keep pushing the boundaries. Can you get stuck in a closing door, or kill an enemy before they are ready to fight you? Can you trigger tutorial messages on top of eachother by completing tasks in record time? Can you get somewhere before the game has had time to draw it, maybe even fall out of the level? Use as many movement exploits as you can find to give you speed boosts, jump boosts and so on. In multiplayer a lot of the time by pushing the game to its limits you will find you can reach an area quicker than any other player or team and benefit from a considerable (and unfair) advantage.

Be curious
Bump into walls. Bump into enemies. Fall off cliffs. Trundle through rivers. Attack walls and lunge into the environment. Try to avoid savepoints, cutscenes, scripted sequences. Jump to supposedly inaccessible areas. Do you fall out of the level? Can you walk through enemies or scenery? Do you get stuck? Do the lighting and other graphics display correctly in all areas? Does the sound play correctly in all areas and on all surfaces?

Be destructive
Break the game mechanics and the game experience. Attack everyone and everything with everyone and everything you can get your hands on: friends, foes, flora, fauna, inanimate objects, breakables, collectibles... everything. Button spam. Spam the pause menu. Spam everything and anything. Trigger as many events as possible at the same time. If you can input text: spam as many characters as possible. Go round the the track the wrong way. Get in people's way. Do things out of sequence (both in-game and in menus). If it's multiplayer: piss people off. Spawncamp, spawnrush, spawnblock: be a hyperactive kid with ADHD.

Single-player versus multiplayer testing
Now, not all of these processes can be applied to multiplayer as equally as single-player. In fact, due to their largely scripted nature on only one machine, it's a lot easier to test singleplayer than multiplayer games that span multiple players on multiple machines all doing completely different things. But, in general, you can apply the same theories to multiplayer, the key difference is that you need to be able to communicate with eachother at all times because a lot of multiplayer bugs come from the fact that people are interacting in unforeseen ways and with unforeseen consequences. For example:

Be a loser
If you don't perform well (for whatever reason: intoxicated, tired, newbie, griefer), will it dramatically affect the enjoyment of the rest of the players? If you get off to a slow start, can you still complete with other players? If you join the game late, can you still compete with other players who have been playing the match from the start? If you die lots does the game get more difficult or are you able to able to improve as you play regardless of number of deaths?

Be fast
Try to discover ways to increase your movement speed. Can weapon knockback be used to gain an advantage? (e.g. rocket-jumping) Can common engine exploits be taken advantage of in your mod? (e.g. wallstrafing, bunnyhopping, strafejumping, scripts) What about running to the enemy as fast as possible; does both side arrive in the middle of the level at the same time, or is there a route that needs adjusting to balance things?

Be curious
Try changing settings during a match. Try quitting and re-joining games; could this be used to gain an advantage in any way? Try joining the other team. Try using abilities at distance; is it balanced? Do third-person animations play correctly and match what the other player is seeing first-hand on their screen? Can all victory conditions be met as expected? Are the victory conditions communicated clearly to beginner players? Can you use any materials (or even other players) to access anywhere you shouldn't be able to? Is all the information you are reading correct? (e.g. scoreboards, weapon/ability/class descriptions)

Be destructive
What happens if you quit the match at different times? What happens if everyone in the game performs an action at the same time? (shoot, micspam, connect to a server, quit the game, change team/class, etc.) Can you spawncamp? Can you obstruct your own teammates? Can you block any paths unfairly? Can you kill teammates? (if so, is there anything in place to deter you from this?). If you go AFK or deliberately hide away somewhere, does the gameplay suffer?