After Alterna

After Alterna is the secret level of Return of the Mammalians. It can only be unlocked after beating all other levels across Alterna.

Access
The kettle for this level is located on Future Utopia Island in the spot where Agent 3 originally landed after falling from the Crater. However, it is not considered to be a Future Utopia Island level for the purposes of the kettles menu and the Alterna Logs, and it cannot be Super Jumped to from the map. Completing the level unlocks the Teddy Band, the Mr. Grizz badge, and the entirety of the seventh and final Alterna Log.

Gameplay
This level is split into four sections connected by launchpads, effectively making it a gauntlet of four separate levels. The only checkpoints are at the beginning of each section and an additional one midway through the third. Each section has a different song; for example, Octoling Rendezvous plays in the fourth section. This makes After Alterna the only non-boss level in the SS undefined to feature more than one song, as well as one of only two levels in to feature Octoling Rendezvous (the other being Bet You Mist Us!).

Section 1
The first section is an intense test of the player's movement abilities. While it is dotted with enemy Octarians, the main threat is the layout of the stage itself, generally requiring very precise jumps to traverse. Octagonal rolling platforms appear in multiple places, including a very large one near the beginning guarded by two Octocommanders, where the player can either hide behind the square walls on the platform or splat the Octocommanders before they get a chance to attack. The stage makes heavy use of the Squid Roll and Squid Surge with multiple obstacles that force the player to use them to progress. There are also multiple obstacles where the player must cling to the walls of moving pillars. Several areas feature multiple inkrails, some guarded by Octotroopers or an Octosniper; if the player moves through these sections as fast as possible, enemy attacks will not hit them. At the end of this section, the player must traverse a "conveyor belt" composed of a cycle of moving blocks close to water. The water does not wash ink off the platforms.

Section 2
The second section consists entirely of ride rails. The player must pop a series of target balloons to cause the next group of rails to appear; if they do not pop the balloons in time or they fail to jump between the rails, they will fall into the water and be forced to retry the section. For the majority of this section, the balloons themselves will only appear as previous ones are popped, with a maximum of three present at once. If the player misses a balloon, further balloons in the series will not spawn until that balloon in particular is popped. At the end of the section, the player is faced with rotating clumps of balloons that travel along with the player concluding with a cluster of balloons that must be shot while the player is in free-fall.

Section 3
The third section makes heavy use of soaker blocks, often requiring the player to use Smallfry to activate them. Similarly to the previous section, this section contains very few solid platforms, and the player must ensure that they traverse the soaker blocks before they disappear. Several types of Octarians appear in this section to hinder this process, often by threatening to attack the soaker block themselves. Immediately before this section's checkpoint, the player must traverse a gauntlet of Octarians atop two extremely long soaker blocks, under the time pressure created by the shrinking platform.

Immediately after the checkpoint, the path is besieged by Octomissiles, and the player is encouraged to block their path using soaker blocks. After a brief climb up a narrow, twisting ramp, the player encounters another Octomissile launcher. The Octomissiles here are equipped with platforms for the player to stand on, and they must ensure that the missile does not explode before taking them to the next platform. The Octomissiles' path is obstructed by a series of soaker blocks that are under constant attack by either Sprinklers or other Octomissiles. The player must deactivate the blocks in order to progress, being careful not to reactivate them with their own ink. To conclude the section, the player must dismount yet another missile, landing on one last soaker block that must be activated by throwing Smallfry (or a Burst Bomb) at the nearby Balloon Fish.

Section 4
The fourth and final section starts on a small platform containing only the checkpoint, an armor pickup, and a launchpad to the main platform. Once the player uses the launchpad, they must fight against three waves of Elite Octolings that use a variety of weapons. Each of the waves consists of a total of ten Octolings, though not all of them are present initially; as they are splatted, more Octolings Super Jump onto the platform. The first Octolings of a wave tend to Super Jump into spots further from the player, while the reinforcements throughout the wave instead try to Super Jump near to them. In each wave, the Octolings will use a different type of sub weapon: Curling Bombs in the first wave, Autobombs in the second, and Splat Bombs in the third. Additionally, the Octolings in the final wave will make use of a variety of special weapons. The main platform rises after each wave, expanding the area that the player can access but also reducing the amount of cover present.

After the first wave is defeated, canned specials will begin to appear for the player to collect. The first can will always spawn on the raised area where the first wave of Octolings appeared; further specials will alternate between appearing there and at the point where the player originally landed on the platform. Each can will only spawn after the previous one is collected. The specials that appear cycle through the following list in order: Trizooka, Ultra Stamp, Reefslider, Inkjet, Crab Tank, Ink Storm, Triple Inkstrike, Tenta Missiles, Ink Vac, Killer Wail 5.1, Wave Breaker, and Zipcaster. If the player collects enough cans for the cycle to restart from the beginning, two armor pickups will appear on the tops of the highest pillars. As these pillars cannot be inked, these pickups can only be collected via use of the Zipcaster. Once the final Octoling is defeated, one final launchpad appears to take the player to the goal.

Quotes
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S3 Icon Callie.png Agent 1green
"Let's get this thing started!"

"WHOA! Keep watching your step, I guess!"

"Ooo, you can ink the bottom half of this pillar!"

"Woo-hoo! Way to fall!"

"You made it! Let's see where that orange takes you."

"Keep it rollin'!"

"PHEW! That was SO intense."

"Should be easy peasy for Agent 3 and li'l Smallfry!"

"Phew! That was nerve-racking."

"Hey, you can finally see the last stop! So close!"

"PHEW! Finally. Commuting is stressful!"

"Is that the goal back there? Like, waaay back there?"

"Uh-oh. Enemies incomiiing!"

"A orange! Yes!"

"Oh, come on! There's even MORE of them?!"

"Wait-why am I worried? You're you! Go splat 'em!"

"Amazing, Agent 3! You really showed 'em!"

}}

{{collapse|

S3 Icon Marie.png Agent 2green
"Whoa! Watch your step."

"Try another orange here. Just check the area above you and time it right!"

"Ooo! You could orange toward the platform here."

"YES! Nicely done!"

"You probably have to pop ALL of these orange, huh?"

"Yeah, great job! You're not done yet, but keep it up!"

"Ooo, there are orange in here. You probably don't need an explanation for those by now, right?"

"I spy an orange. Be careful up ahead!"

"All aboard the orange commuter train..."

"The end of the stage must be at the last stop... but I guess that's obvious, huh?"

"OK, time to move!"

"Nice work. Let's move on!"

"Just three enemies left!"

"Was that all of them? I think that was all of them..."

"What? There are more of them?!"

"Only three more to go. Be careful!"

"Look! Each time you grab a can, the next one appears on the other side."

"Hmph! That was the last of 'em, right?"

"Only three more. Don't slow down now, Agent 3!"

"Seriously! You were SO fresh out there. Congrats!"

}}

Trivia

 * After Alterna's gate has a unique song that is not used for any other gates.