Super Mario Bros.: Super Mario Bros : Fourth Quest

Super Mario Bros : Fourth Quest takes on the idea of a 'bonus quest' after beating the first quest, introducing:

Instant Kill Dark Koopas, in all flying variants replacing Green Koopa who cannot be stomped and is immune to fire.
Spiny Beetle from the inspired ROMhack "Super Mario Bros Third Quest" replacing buzzy beetle who cannot be stomped.
Horizontal Podoboo replacing Bullet Bill who cannot be stomped.

The Velocities of the enemies have increased on average and the projectile frequency has also increased to make more difficult to beat.

The Hard Mode replaces all Goombas with Spiny Beetles with faster velocity.
Sprites have been changed to be more red in general with no graphical edits other than the described above.

This will work alongside any Level or Music hacks, graphics hacks may cause some issues and no compatibility is garunteed.

Database match: Super Mario Bros. (World)
Database: No-Intro: Nintendo Entertainment System (v. 20210216-231042)
File SHA-1: EA343F4E445A9050D4B4FBAC2C77D0693B1D0922
File CRC32: 3337EC46
ROM SHA-1: FACEE9C577A5262DBE33AC4930BB0B58C8C037F7
ROM CRC32: D445F698