Good luck! I wrote down some notes which will hopefully help you improve the game.
– First of all, outstanding graphics. I like the colourful toon style.
– Yellow font in the menu is bright, the background behind is also bright, so it might be better to choose a different color for readability. Also consider changing the font, this one is more suited to small handwritten text (e.g. a letter), but in the menu, you want the options to stand out. This is especially case of the score count (if you wish to track score), the number in the corner is quite small in comparison with everything else (e.g. the heart counter)
– "Credits" are cool :)
– "Exit" button is unnecessary in a web build, it does nothing
– For a platformer game, your jump height is pretty low and so is the gravity (you jump up quite fast, but it takes ages until you land back on the ground. Even if you walk off a road to the water, you sink in very slow). You can even continue walking in mid-air.
– Add a splash sound when you touch the water
– Add a sound when collecting a coin (or any graphical effect when collecting it, so it doesn't just instantly vanish)
– The grass appears gradually, that's fine, but the boundary is too close to you. Ideally, you shouldn't notice the appearing and disappearing, it might feel intrusive
– Music doesn't loop
– Improve collision detection
• Trees and rocks don't have any colliders
• Player's collider is too large (you can stand next to spikes, don't even touch them and still get hit)
• Player's feet are sunk into the ground a bit (enlarge ground's collider?)
• When you go towards a wall, you can pass through without extra effort
– "F" as run key is a bad decision. The way you hold WASD leaves you to a choice between walking right and running. "Shift" would be much more logical and comfortable option.
But in my opinion, this is a platformer and you want to be running most of the time, so I'd make "run mode" default and holding Shift/Ctrl as "walking".
– After game over, the load button should be inactive (greyed out). Now it works and (apparently) loads the menu scene (judging by the small lag when you click it). And nobody needs that.
– If you're not in the fullscreen mode, text in game over screen is broken into more lines (e.g. Game *newline* Over, Main *newline* Menu)
– When you die, the enemy who followed you returns to his original spot. That's okay, but he flashes back *while* you're dying. He should wait until you return to your respawn position
– The rabbit doesn't cause any damage, his "follow player" distance range is too small and when you run away, he "pops" in a different place and starts walking again
– You should try to be consistent. If your hero is a medieval warrior, your enemy is a medieval warrior, a creepy rabbit out of nowhere may seem like somebody tried to mash up several free assets together and the game won't have an identity, world of its own. I'd ditch Mr. RabZ. :)
– Walking over a dead enemy (not the rabbit) makes sound every time. It probably shouldn't.
– The sword swiping sound is fine if you hit an enemy, but swiping a sword through plain air doesn't make this "cutting flesh" sound. Check freesound.org, there's plenty of "whoosh" sounds you could use
– It's great you've added some birds as a background. Sometimes they fly too far away, maybe, but it's a great idea.
– Spikes' up/down cycle is too fast to pass over them without harm. Now it's okay because you just need to avoid them, but later if you added a batch of them in the player's way to walk over them when it's "safe", it probably wouldn't be possible. There could be e.g. a second long pause when they're inactive
– Being stabbed once with a sharp metal (spikes) certainly doesn't make a "BAM BAM BAM" sound
– Spikes harm you only once, even if you stand on top of them. In Unity, instead on "OnCollisionEnter/Exit" like you probably use to not deplete player's health all at once, you could harm player always at the specific time of the spikes' animation if he touches them (create an animation event). Or simply use the animation event to set whatever "spikesCanHurtPlayer" bool variable you use back to true, so it will harm the player with each push.
– You don't move with moving platform. You could either add the platform's velocity to the player's (hard solution), or simply set the player's parent object to the platform when he touches it, and to null when he leaves.
– Moving platform passes through ground. Either lower the ground or relocate the platform's end target point.
– Trees stick through the platform above them
– The interval of disappearing platforms might be too short (impossible if you don't run) and most importantly - they don't reappear. Fall off a disappearing platform and you might as well restart the whole game.
And it's always good when you can tell a platform is just about to disappear, so it doesn't come as a surprise. Some games add cracks, but you could make the platform slowly fade out (gradually change the platform's color's alpha to zero).
– Consider building the game as WebGL, so everybody can play it, not just Firefox / Explorer users who installed a plugin.
https://www.newgrounds.com/wiki/developer-resources/unity3d-webgl-support#wiki_toc_3
Anyway, as you can see, there's still some work left to do, but I'll repeat that I quite like your game and think you are on good way to make this a really neat platformer. :)