That’s a strong foundation for a browser game. The part of Dangerous Dave worth copying isn’t the exact mechanics so much as its economy: very few controls, instantly understandable rules, short levels, precise movement, secrets, and escalating difficulty. A modern version could preserve that while adding one distinctive mechanic that gives the game its own identity.
I’d design around these constraints: left/right/jump + one action, levels around 30–90 seconds once mastered, instant restart, pixel-art presentation, and no sprawling upgrade/inventory system. The player should understand almost everything within the first minute, but still be discovering techniques much later.
A concept I think could work: DEAD AGAIN
You’re a tiny escaped test subject working your way through a malfunctioning underground facility. Visually, think chunky EGA/VGA-era graphics: black backgrounds, cyan/magenta machinery, spikes, acid, lasers, doors and absurd little monsters.
The unique mechanic is that every time you die, your previous attempt remains in the level as a ghost that repeats exactly what you did.
So initially it feels like Dangerous Dave:
← → move Space jump X interact/fire
But death gradually becomes part of solving the level.
Suppose there's a pressure plate that opens a door. You run onto it and die. On your next attempt, your ghost repeats that run and stands on the plate while you go through the open door.
Later:
Ghost #1 activates a lift. Ghost #2 attracts an enemy. Ghost #3 gets killed by a laser and temporarily blocks it. You use all three to reach the exit.
That creates an interesting contradiction: dying is useful, but dying too much makes the level increasingly chaotic.
And importantly, you don't need to explain much of it. Players discover it.
The Dangerous Dave structure
Each level has three objectives.
Find the key/artifact, reach the exit, and optionally collect every treasure item.
You can finish without collecting everything. But completing the entire game requires finding all the hidden collectibles.
I'd make perhaps 40–50 handcrafted levels, divided into five visually distinct areas. The first ten would be almost embarrassingly simple. By level 40, players would be performing ridiculous sequences using several previous versions of themselves.
But there should be no procedural generation. The appeal is learning beautifully designed levels.
The difficulty curve should feel like:
Level 1: “Oh, this is easy.” Level 5: “That's clever.” Level 12: “Wait—I can use my dead guy to do THAT?” Level 25: “This is evil.” Level 40: “There is absolutely no way.” Five minutes later: “OH.”
That last reaction is what I'd optimise the entire game around.
The addictive element
Don't make progression itself grindy. Make mastery addictive.
Every level records:
TIME 00:41.83 DEATHS 3 TREASURE 7/7 SECRET ✓
Then reveal a tantalising target:
PERFECT: 00:28.00 / 1 DEATH
So somebody can casually finish a level, while another player spends an hour trying to perfect it.
There could even be a wonderfully cruel achievement:
ALIVE AGAIN — Complete the entire game using the theoretical minimum number of deaths.
That makes full completion genuinely difficult without making ordinary progression miserable.
The ghosts also naturally produce speed-running possibilities. Expert players could intentionally die at very precise moments to create an optimal sequence.
One other ingredient I'd steal from early PC games
Secrets that aren't signposted.
A wall that looks completely ordinary can be walked through. A treasure appears if you jump somewhere pointless. One level has a second exit. Perhaps entering a particular sequence of rooms takes you to something bizarre.
Modern games tend to telegraph secrets with cracked walls, glowing objects and UI indicators. Don't.
You want schoolyard-style:
“Did you know there's another level behind the wall in Level 17?”
For a browser game, that kind of discovery is particularly valuable because players can immediately send someone a link.
Keep the fiction stupidly simple
I'd resist lore, dialogue trees and lengthy introductions.
Opening screen:
YOU HAVE ESCAPED. THIS WAS A MISTAKE. [ PRESS SPACE ]You're playing three seconds later.
The character should also be visually tiny and memorable—something you could recognise from a 16×16 sprite.
I think the death/ghost mechanic + brutally compact platform levels + hidden completion layer has enough depth to make this substantially more than a Dangerous Dave clone while retaining exactly the simplicity you're after.
And because you mentioned wanting it unique, I'd spend most of the design effort on that single mechanic rather than adding guns, inventories, crafting, character classes, etc. One brilliant rule exploited 50 different ways will feel much more like the games from that era.
Which direction appeals more: A) death/ghost puzzle-platformer, B) faster action/platformer with a different signature mechanic, or C) much closer to Dangerous Dave with secrets and new hazards?