STEINS;GATE RE:BOOT Walkthrough – Complete 100% Route

To 100% STEINS;GATE RE:BOOT, play Chapters 1–10 once for Mayuri’s ending while collecting Phone Trigger extras, then reload from Chapter 4 for Kurisu flags, then Chapter 10 for the true ending. Save before every Chapter 6–9 D-Mail / PhoneWave prompt.

This page is the route hub. Use True Ending for the six flags, Email Choices to Ctrl+F a subject, and Achievements for missable trophies. Achievement replies and true-ending replies are different chains — do not mix them.

Ending branch map

Chapter	If you stop here	Continue by	Trophy
6	Suzuha ending	Send the D-Mail	Irreversible Reboot / Metaphysics Necrosis
7	Faris ending	Send the D-Mail	Isolated Jamais Vu / Made in Complex
8	Luka ending	Call the PhoneWave	Link of Corruption and Rebirth / Fractal Androgynous
9	Moeka ending	Send the D-Mail	Hide in Darkness / Endless Apoptosis
10 + 0 flags	Mayuri ending	—	Stardust Sky
10 + 1–5 flags	Kurisu ending	—	Paradox Meltdown
10 + all 6 flags	True ending	—	Open The Steins Gate

Quick saves exist at the start of each chapter if you skipped manual saves.

Minimal save-slot plan

You do not need dozens of permanent saves. Keep a small set at the decisions that actually create expensive reloads:

Save	Make it here	What it protects	How to use it
A	Chapter 4, before Kurisu’s `Did you write it?`	Cup-noodle achievement vs True Ending Flag 1	Take the achievement branch, reload, then start the scientist flag chain.
B	Chapter 5, before Mayuri’s `What made me happy today`	Two mutually exclusive achievement replies	Take `cosplay`, reload, then take `Fubuki-chan and Kaede-chan`.
C	End of Chapter 6	Suzuha ending	Do nothing for the ending, reload, send the D-Mail to continue.
D	End of Chapter 7	Faris ending plus Chapter 7 mail splits	Take the ending, reload, then continue after finishing any Flag 3 / Froggy side branch you need.
E	End of Chapter 8	Luka ending	Do not call for the ending, reload, then call the PhoneWave.
F	End of Chapter 9	Moeka ending	Do nothing for the ending, reload, then send the D-Mail.
G	Chapter 10, before `Where are you now?`	Kurisu vs True ending	Ignore the mail for Kurisu, reload, then reply `Where you are` for Flag 6 and True.

If you only care about the story endings and not every mail collectible, Saves C–G are the essential branch points. Saves A–B are what prevent achievement cleanup from turning into another long replay.

Prologue

Clearing the prologue grants Prologue of the Beginning and the End. No email flags.

Chapter 1

Quick route. Read normally. On the PhoneWave timer, type garbage ten times for Homerun-level Clumsiness, then enter 120# to continue.

Phone / collectibles. Open sent mail (Memories of the Self), open received mail (Memories of Another), change wallpaper (Vision Projection), change ringtone (First Sound).

Emails.

Sender	Subject	Reply	Result	Type
Mayuri	Upa…	Upa. then Kakeru-kun	Resonant Reaction; RaiNet’s Mascot; first RaiNet batch	Achievement + Collectible
Faris	The decisive battle is close at hand nya	Red Southern Cross	Progress on Princesses of Chaos (finishes in Ch.5)	Collectible

Chapter clear: Time Travel Paranoia.

Chapter 2

Missable calls. Mayuri, then later Kurisu. Ignore any call in the game for Identity of Complete Isolation (save, ignore, reload). Answering Mayuri adds a Mayuri + Faris scene. Answering Kurisu puts her in the Yanabashi Shrine scene.

Emails. Lukako I made sweets. → Family. You only get About my family members. if you answered Mayuri on 8/01 14:29. Reply My sister, then read About my sister. for Cruel Sister.

Chapter clear: Interpreter Rendezvous.

Chapter 3

No ending branch. Daru calls: answer for Daru + Mayuri, ignore for a Kurisu scene.

Start the Gero Froggy chain: Lukako About Frogs → Gero Froggies, then open the attachment.

Faris PHANTASM is the cat's meow starts more RaiNet summaries.

Chapter clear: Butterfly Effect’s Divergence.

Chapter 4

This chapter has two Kurisu chains. The cup-noodle chain is an achievement. The scientist chain is True Ending Flag 1. You cannot treat them as the same path — save and do both across reloads, or do the achievement path on the Mayuri run and the flag path on the Kurisu-flag run.

Achievement path (not the true ending).

Sender	Subject	Reply	Result
Suzuha	Akihabara’s	peaceful	Warrior Girl’s Pride
Kurisu	Did you write it?	Report → Cup noodles	Discontinuous Qualia (read Favor to ask)
Faris	Sign of increasing misfortune	He → NyanNyanian	Cat’s Tea Time (read Cat tongue nya)

True Ending Flag 1 is documented on True Ending. 25% CG trophy can pop here.

Chapter clear: Chaos Theory Homeostasis.

Chapter 5

Faris calls at the start: answer for a Faris extra scene, ignore for a Mayuri extra scene.

Mayuri mail needs a save. Subject What made me happy today:

Reply cosplay → read The reason → Passions Best Forgotten.
Reload. Reply Fubuki-chan and Kaede-chan → read Huh? → Princesses of Chaos.

Flag 2 is Kurisu Plans → Traveling expenses (see True Ending). KKB also notes a Chapter 5 extra scene with STEINS;GATE 0 flavor — story detail stays on the differences page.

Chapter clear: Dogma in Event Horizon.

Chapter 6

Optional calls. Not calling Mayuri at the start adds a scene. Later you can call Mayuri or Lukako. When offered Kurisu / Mayuri / Daru, calling one adds that scene; doing nothing adds Suzuha instead.

Save point. End of chapter, D-Mail prompt.

Do nothing → Suzuha ending / Irreversible Reboot.
Reload, send D-Mail → continue. Chapter clear Metaphysics Necrosis. 50% CG can pop.

Chapter 7

Kurisu calls: answer for Kurisu, ignore for Faris.

Froggy batches 2 and 3 live here and need Flags 1 and 2 already. See Gero Froggy. Flag 3 is also here.

Save point. D-Mail prompt.

Do nothing → Faris ending / Isolated Jamais Vu.
Send D-Mail → Made in Complex.

Chapter 8

Straightforward until the end. Flag 4: Kurisu Explain yourself! (only one reply), then read From an unpopular girl.

Save point. PhoneWave prompt.

Do not call → Luka ending / Link of Corruption and Rebirth.
Call PhoneWave → Fractal Androgynous.

Luka’s final act is reworked versus older versions (see differences).

Chapter 9

You can call the PhoneWave or skip for an extra scene where Kurisu calls — answer for more Kurisu, later ignore a second Kurisu call for a Moeka extra scene.

Save point. D-Mail prompt.

Do nothing → Moeka ending / Hide in Darkness (Gamma worldline — full page).
Send D-Mail → Endless Apoptosis. 75% CG can pop. Flag 5 is Contact me, idiot! → Worried.

Chapter 10 / Mayuri, Kurisu, True

If you followed this page without Kurisu flags, you get Mayuri ending / Stardust Sky.

For Kurisu vs true ending, jump to True Ending. Completing every ending grants All Worldlines Complete. Full CG grants 100% CG Achievement. Playing through everything grants Sky Clad Observer.

Cleanup if needed: Message of Oblivion = leave mail unread and finish the chapter or change worldline (KKB suggests a Chapter 6+ skip). After the true ending epilogue, see Secret Post-Credits Scene.

Verification after the September 7 update

The official September 7, 2026 Steam update addresses audio not playing on Steam Deck and notes continued Steam Machine compatibility work. It does not announce changes to the chapter branches, Phone Trigger reply chains, ending requirements, or the six True Ending flags documented here. On September 15, this route was rechecked against the current Kiri Kiri Basara 100% guide, the Steam store, and the live achievement list rather than simply carrying the launch-week verification date forward.

Last verified: September 15, 2026. Steam app 4012810. Uncertain items are marked not yet confirmed.

Sources

Kiri Kiri Basara 100% Guide (Martin, 19 Aug 2026)
Kiri Kiri Basara review (13 Aug 2026)
Kiri Kiri Basara Digital Deluxe review (15 Aug 2026)
Official English site
Steam store
Steam achievements
Steam Community — September 7 update
Videos used as research (facts extracted, not copied): KKB 100% Guide, KKB review, Noisy Pixel review

STEINSGATEREBOOT.site is an unofficial fan-made guide and is not affiliated with MAGES., Spike Chunsoft, or the game’s rights holders.