Worlds

Waterfall

Third region, and the update that added the Underpass.

Waterfall in [🎉RELEASE🎉] Undertale Adventures X

Waterfall: Third region, and the update that added the Underpass. Get it by Update shown as playable on September 21, 2024. Use it to Bring a unit that can hit flying enemies on Act 6 if that wave still opens the same way. Underpass XP is documented on its own page.

What is Waterfall?

Waterfall was shown as a new map on September 21, 2024, with a Waterfall summon, the Underpass track, and a 25-wave anniversary raid that paid candles for gift skins. Act 6 Neutral footage from September 25 starts with flying enemies and longer waves.

Published facts

Waterfall facts
FactValue
When it was shownShown live in footage published September 21, 2024

How do you get Waterfall?

Update shown as playable on September 21, 2024.

How do you use Waterfall?

Bring a unit that can hit flying enemies on Act 6 if that wave still opens the same way. Underpass XP is documented on its own page.

FAQ

Waterfall questions

What is Undertale Adventures X?

It is a free Roblox tower defense experience by Side Productions. You defend a base with Undertale-inspired units, level those units, and strengthen them with traits. The experience was created on July 16, 2024, and the public record was updated on October 12, 2026.

Is Undertale Adventures X free?

The Roblox listing has no paid entry price. Optional Robux gamepasses exist. Known names include VIP, SHINY Hunter!, Supporter, +50% Tokens, and 2x XP. Current Robux prices were not on the public listing text used here.

Who makes the game?

Side Productions, the verified Roblox community that owns the experience. The community page is linked from the game listing.

How do codes work?

Open the Codes button on the right side of the screen, enter the full string, and press Enter or Redeem. Only 2KCCU! and FREESTUFF! were still reported working in October 2026, and both rewards were described only as freebies.

Do trait rates still match the old table?

Trait rerolls assign one of 12 listed traits. The rate table matches an August 2024 odds screen for Royal Guard Soul at 15%, and a November 29, 2024 video described the Perseverance buff the table now shows. Read the percent in your own Traits menu before you spend a large stack of rerolls.