Should it be a quick intro to the game? Or should it be something that will make the player laugh and get hooked so that they watch the whole trailer?
Also, would 2D animation be better, or 3D animation?
I am asking this because I am trying to make a trailer for my game, I have friend who is a 2D Artist who is learning animation who would do it for a low price.
I know this post is short 
It should really be something that the player can get hooked onto.
If you’re going to make a game trailer, don’t make it to misleading like saying you can fly but you can only hover in the game, also the game trailer type is all about what genre and who is most likely going to play the game, like if you were going to make a serious RolePlay game, usually make it concise and brief. Whilst a simulator and a game leaning towards a younger audience will work much better if it’s a funny animation that hooks them into it (it’s the same reason why Cocomelon (A kid-friendly youtube channel) is even popular to children, it’s grabs their attention REALLY well and makes them entertained).
3D animation is considered to be more professional in some cases but if done well, 2D animation is MUCH better.
I actually found the perfect video for this questions.
Find it here.
It is a 15 minutes video explaining how to make a good game trailer, also if you have the chance, look at some of their other videos about game design and what not, really neat stuff.
I noticed that a lot of game trailers that were rated good had a bit of humor in it, such as arsenal. I am not an expert, but I suggest some humor!
Also, if you didn’t already know, the trailer has to be under 30 seconds for Roblox to accept it. I found this out the hard-way, I fixed it but then roblox moderated it. So make sure to stay under 30 seconds! Also, humor is good, if your game is 2d then 2d, if your game is realistic, 3d. Finally, make sure the animation looks real and not choppy, it looks unprofessional.
I wouldn’t recommend making the trailer on how to play as that can be boring to the player. I think you should totally choose a humorous genre.
From my experience it doesn’t always need to be an animation. A in-game footage without too much editing (only music and cutting certain parts included) is the best for a game as you show the player the real beauty of the game and it especially works in FPS games. As an example, I’ll show you the pre-trailer made for the game Blackhawk Rescue Mission 5 which is already release, but the Developer published it before the game as a hype trailer. (https://www.youtube.com/watch?v=1WU5UQGq0gs)
Indeed, the video is almost 4 minutes long, tho with good editing and cutting some parts you can adjust it to 30 seconds and make it very exciting, giving users the hype to join it immediately!
There are some cool Roblox game trailers over the years.
R2D (my favourite): https://youtu.be/hIEu5IPCKtA?t=8
Stop it Slender: https://www.youtube.com/watch?v=udbInhWAS4c
Speed Run 4: https://www.youtube.com/watch?v=TUxDy88VCKY
R2DA: https://www.youtube.com/watch?v=nkdNxYqItq4
Those are some examples I could list from the top of my head.
These examples are simply just collages of game footage. The Speed Run 4 one showcases the levels. Stop it Slender tells you how to beat the game and it’s kinda like a real horror game trailer. R2D and R2DA trailers kinda show the maps and killing people/things.
This might interest you
There are many ways you can make a trailer, and that, of course, brings many reactions. But I’ll give you an example of how a trailer made me fall in love with a game to the point where I watched everything about the game until I was able to play it.
It’s TF2. To me, what made me get hooked into Team Fortress 2 was one of the best trailers (or showcase, or video) that they’ve made about it, and you can see it because it get’s memed a lot. Meet the spy. Seeing how very few characters were able to communicate humor, interaction and character design in one video, while also showing how cool that character is, is what made me want to know what it was about. Even more when they made trailers for more characters and more ways of playing without telling you how to play, just show what they can do. I personally knew about meet the spy because of a meme video, but that’s irrelevant
If you see the meet the spy video, and you get hooked into it the same way I was, it would mean that you’re into the same type of games I am into, which doesn’t help much, but it would help you define what audience would play your game.
From seeing that trailer, mixing comedy (look for comedy well, don’t try to make it forced or badly made, just something of mild humor), action (if the game involves action), showoff (showing something that the players would like to do, which can be done inside the game) and a small story, something easy to tell, would work well.
This is more the opinion of a member of an audience. If it fits your game, then it could work…
If you’re going to do a shooter trailer, make it intense.
Usually, you can hook people with rhythm-synced shots and lots of action.
Let the player get hooked, be sure the visual/audio quality is good.
If you can get 2d for a cheap price, you should take it. You can always make a different intro later on if needed!
Some dramatic style you should add, with epic montage. You would have to give people interest on your game by adding like “DESTROY, BUY, KILL!!!” messages (you can write other messages about the game instead of the quotes), video record clips of your game, add reviewing clips on the video (store guis, gameplay and etc)
Hope you will appreciate it!