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Modify: YES - Maintain: YES - I give permission for my entire submission to be modified by others or used in their own work. I give permission for my entire submission to be maintained by others as well.
This is rphys, a custom build containing a total overhaul of the game physics. The changes are essentially:
Global Physics
  • Momentum is preserved
  • Linear acceleration
  • Slope physics are drastically altered
  • Higher gravity, higher jump heights
  • More maneuverability while jumping or spinning
  • Reworked airwalk to only happen under certain conditions
  • Super transformation is now done via the FIRE button



Ability: Trick Spin
Double jump to charge a drop dash. Release jump in the air for a speed boost or keep holding it for a larger speed gain upon landing. You can also spin up walls by colliding with them.

Tip: After spinning up a wall, there is a short period where you can use the Trick Spin a second time.



Ability: Fly
Double jump to start flying for a limited time. Keep holding the jump button to ascend. Keep holding the jump button to ascend at the cost of speed.

Tip: The flight timer only decreases while Tails is actively flying upwards.



Ability: Glide & Climb
Double jump to glide in the air as long as jump is held. Glide into a wall to climb it.

Tip: Jumping off a wall will point the camera away from it. Press spin instead to jump without changing the camera.



Ability: Hammer Spin
Hold spin in the air to rotate rapidly and fall faster. Hit the ground for a speed boost.

Ability: Whack & Roll
Press spin on the ground to swing Amy's hammer into a roll.

Tip: Strike a spring with any hammer action to increase its power.



Ability: Tail Bounce
Double jump to bounce off the ground and most hazards as long as jump is held. This can also destroy some floors.

Ability: Pop Gun
Press spin to fire a cork at the nearest target. You won't be able to move while firing.

Metal Sonic


Ability: Jet Burst
Double jump to to perform an air thrust which gets stronger during dash mode. Keep holding jump to reduce the effects of gravity.

Ability: Quick Roll & Speed Booster
Press spin on the ground to perform a somersault. Gain dash mode to change this ability into a booster while spin is held.

Ability: Dash Charge
Hold spin while idle to charge dash mode.

Extra Notes
Source code: https://git.do.srb2.org/katsy/SRB2/-/tree/rphys

Certain maps may have issues due to the higher gravity. Also, don't even look in the general direction of Axis2d. Just don't do it.

The majority of custom characters should work fine.

Lua can check for the global rphys to detect this mod's presence.

CobaltBW: aerial popgun sprites, original turning code

Chrispy & Lach: sparkles from chrispychars

Logan McCloud: sprite replacements

SuperPhanto: peelout sprites

Krabs: ring sprite

DirkTheHusky: dropdash sprites
First release
Last update
3.18 star(s) 11 ratings

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Latest reviews

the physics feel clunky
sonic feels unintuitive the "thok" is too slow the "drop dash" part feel like it should have been mapped to spin
tails feels stop and go
knuckles felt more clunky than usual
amy is a completely different character
metal is just old sonic w boost mode
and finally fang feels pretty good being able to shoot at any speed is nice
overall i severely disliked the addon despite the effort put in
Upvote 1
the mod seems to be like a classic sega official game i love the almost perfect momentum
Upvote 0
it is so fun launching myself into space with every character
Upvote 1
This is amazing, and since its hardcoded, you dont need to go through the trouble of searching for it through your addons folder.
Upvote 1
It's a good gameplay overhaul

Great abilities and new colors...
One thing that i found strange is that, on version 3 I'm having problems to play with my friend online, he's getting alot of resynch, when I hosted in version 2 this didn't happen.
Upvote 1
This feels great to play! While not perfect, it definitely feels more natural to control than vanilla SRB2. If you liked reveries, you'll like this mod too. I love the new physics including the new acceleration and slope physics. Version 3 in particular feels great compared to the previous versions. Version 2 was fun but a bit too slippery, and Version 1's abilities weren't exactly my favorite. That's why I bumped the rating up from three stars to four.

However, there are still issues I currently have:
- The characters can jump unnaturally far which makes it harder to control. Try adding some sort of air drag (even if it's weaker than the classics).
- I'm worried that rolling may be too powerful. Try adding rolling friction back to nerf it.
- With Sonic's new trick spin, you can easily lose control since there is no limit to how powerful the ability is. Try adding some sort of cap, even if it's very high.
- I'm not sure if Fang's pop gun is fun enough to use, mostly because it slows you down when you use it. Try making it so that using the pop gun doesn't slow you at all.
- I'm not a fan of Metal Sonic's Rush Thruster at all. I'd rather have some sort of vertical thrust to compliment Metal Sonic's boost mode.

Overall, I think this mod deserves more attention and praise for what it sets out to do. Good luck to you in the future!
Upvote 0
The mod doesn't work
Upvote 1
Interesting momentum mod with new abilities.
Although physics itself is slippery, everyone's getting a little uncontrollable with high speed, so it kinda spoils the impression.

Abilities also interesting enough, I like Sonic's abilities the most, that's a really cool idea to mix Thok and Drop Dash at one ability.

Fang is also fun enough, this Bounce Tail's buff is awesome.

Amy's abilities is weird, but it has good potential with her Athletics-ish tricks. That is really weird that she can't do good badnik bounce at all, Ig that's for balance, so that she couldn't OP badnik bounce with her cyclone hammer.

Metal's abilities is interesting one, I like more controllable version of boost mode, but again, it all spoils slippery controls because of physics.
Rush Thruster is also weird, quite a risky ability to make any mistake like fall to pits, spikes and so on. I can't even cancel this ability, although I think it would be very useful and make Metal more fun.

Tails and Knuckles just have good balance buffs, I can't say anything about that.

Overall, definitely interesting mod with some good ideas, but this physics isn't really good enough to play comfortably.
Upvote 2
The abilities are not working please help
Upvote 0
Some of the physics changes are nice, like the slope momentum and linear acceleration changes, but the air and rolling control puts me off of it. When you make spinning and jumping physics just as snappy as the ground physics, it makes it really hard to jump or roll into enemies at high speeds, since you can't make fine adjustments. Also I just don't really like the idea of sonic having a double jump. It just feels wrong for some reason, like its some b-grade 3d platformer from the early 2000s or something.

There's a lot of potential here, though. I feel like a middle-ground between how this and vanilla SRB2's physics work would be perfect.
Upvote 2