Is there an expected length in levels to a platform game? Like a certain length needed to engage the player?

I'm making a game about as fast-paced as Sonic and since I'm designing the art assets, and the resolution isn't very small, I find it hard to supply track. So my levels end up lasting about 30 seconds.

Levels in a Sonic game are about 2-3 minutes long, by the way. And contain multiple paths, which my game doesn't.

While we are on this subject, a problem of mine is just, I can't make the games I develop long. I'm not sure it's laziness so much as design issues. For example, an explorational RPG I made with a 1 hour length could have lasted 15 hours had I implemented grinding. But I also dislike repetition - more so in the games I make, than as a player.

i think there is some reason in side scrolling arcade games like sonic mario or rayman that are short. first reason is as i read in some articles your brain just can take excitement just for some minuets and aftter that its hard and not fun. in games like call of duty that levels are longer they give you fight for about 5 6 minuets and for a little time rest and in that time you have story and its longer because its for older group of people. in arcade games you dont have much story and there is no reason for it. next reason i think is longer levels maybe cause more hardware use and you have to do level streaming that some part of game loads in middle of level and most of the time you dont want it. that is my idea. i hope it helps.

Really escalate the learning curve throughout the level design if its going to be short, if it's short then players don't mind it being pretty tough. Extending the levels means exploration and new design ideas players haven't experienced. Players take new challenges slowly, either because they rush in and fail or actually slowly to work out mechanic. If the level only takes 30 seconds try digging a little deeper into the design ideas your putting into the level try and expand on the ideas that are getting the best feedback. Watch players as they play test your level and look for hints of emotion (any) and make notes at those parts. Then bring some ideas back to the forum and brainstorm expansion ideas.

It's probably best to vary the length from level to level. Donkey Kong Country: Tropical Freeze begins with a fairly long level - around 8 minutes on the first play through, but other levels might be as short as a few minutes. If you wish to have levels that are quite long (about 4+ minutes), then you'll have to find ways to vary the level visually and gameplay wise so it doesn't make the player weary partway through.

30 seconds is too short. Also, by not putting in any multiple paths, you diminish the replay value of your game, which is a very important factor in gaming. Hidden areas, rewards for high scores, multiple pathways, all this kind of stuff makes the game more fun and more replayable.

This is an interesting subject. I haven't seen any literature on it.
To contrast with the finite-level paradigm, there are some games with continous levels.



The game Another World is a 2D platform game that does not scroll and is consisted of several screens.
Apart from cutscenes and parts of the game that prevent you from returning to previous screens (for instance, you've fallen from an opening on the ceiling and can't get back to it), the game has only one "level" that is continuous.
There must be an internal structure to the level, defining sections as ranges of screens. Any time you leave the game or die it saves your progress and the next time you play it, you're returned to the starting screen of the section in which you were last located; it is usually a neutral screen that doesn't have any enemies or time-dependent obstacles. These could be considered as checkpoints.



Another, more recent game of this style is Limbo. It's a side-scrolling platform game. There is only one continuous level and some parts of the level prevent you from returning to the previous parts. It also has internal checkpoints for saving your progress and restoring it after you die or restart the game.

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The lack of finite levels sounds like a good idea for my game, where levels would be 30 seconds on a finite-level system.

The only downside I see is that taking away finite-levels seems to maybe take away a "level select" screen, which to me adds to the presentation value of a game.

You could say that having a single continuous level leads to a more immersive and cinematic experience, if this is what you're after. This also comes from the fact that both those games have no form of in-game GUI or textual information.

The only downside I see is that taking away finite-levels seems to maybe take away a "level select" screen, which to me adds to the presentation value of a game.

It is technically practical to store each game state in a save file as the player passes through each checkpoint in the level. Then you can present each checkpoint for the player to select and replay as chapters in a "Chapter Select" screen. All of this while still under that continuous level model; I don't think that these features contradict each other.
You can also not use fixed checkpoints and rather have a manual save\quick-save feature that the player can use to save game states. When the player goes through certain points in the game you can create an automatic save for that point, but the player is also able to save at any intermediary point he desires.

In either case, you can also display a small screenshot or "thumbnail" of the how the game state looked like at the time when the game saving happened.

I say add a free roam or open ended-ness. Imagine that, running along in a world where there are npcs, side quests, and stuff like that. Maybe I could go so far to say that you could add the ability to invade randomly generated towns, have space ships to roam across a giant world, star coordinates to go to different worlds, and maps to find different cities. Rain hell from a cruiser thousands of feet in the air, and be able to walk around in the ship. I dunno, platformers can have so much potential. The things I could do if I had a game studio...sigh.