Gatekeeper Co-op Guide

Table of Contents

Boss Mechanics
Team Comps
Week 2 (Fire Weakness)
- Modernia Reload team
- Roles

Ranked Co-op is here! It is extremely recommended that you play with friends or guildmates to better coordinate team comps and strategy if you want to have a high placement in the rankings. Unfortunately, this does not apply to low leveled players as after stage 9, Gatekeeper will more often than not just one shot the team (but the mechanics do stay the same though). This guide is aimed towards players who want high scores for flex purposes or higher placements in the leaderboard, or just for players who want to have fun while knowing how the boss mechanics work.

Actual badass intro

Boss Mechanics

Shield

Bring at least one water unit to deal with his bubbled QTE circles. Non-water units are unable to hit through his shield that he covers himself with, showing hits toward Gatekeeper as “Immune” while water units do not have such problems.

Failing this QTE will punish you with a AoE damaging move that does hurt quite a bit

Week 2

Bring at least one Fire unit to deal with his bubbled QTE circles. Non-fire units are unable to hit through his shield that he covers himself with, showing hits toward Gatekeeper as “Immune” while Fire units do not have such problems.

Stage 9 > Transition

Red circles are your enemies, white circles are your friends. DON’T hit the white circles or time out, you’ll get heavily punished for doing so as the boss throws a literal sun at you which can easily end runs.

Wormhole

There is no way to prevent this move except stalling it a little bit by destroying rings, which is not worth it as all the rings will spawn promptly, technically increasing boss DPS. only elements that exploit gatekeepers weakness can hit through the bubble.

Rings

These 4 rings (up, down, left, right of Gatekeeper) are the consistent damage dealers from the boss, If you don’t get taken out by failed QTE’s, attacks from these will. They become extremely tanky beyond stage 9, and deal pretty damage as well. Destroying these rings will reduce the amount of damage Gatekeeper deals. Keeping 1 ring alive is recommended if you have trouble surviving, as destroying all rings will have all the rings respawned shortly after.
You are able to and should reduce the HP of all rings before they become extremely tanky after stage 9 transition (Destroyed rings will be respawned).

Leaving all rings at very low HP and then finishing off 3 rings, leaving 1 ring alive after transition will greatly improve survivability.

Meteors

It is recommended to use AOE burst (Scarlet/Privaty) to get rid of these, face tanking meteors will cause DPS loss as the Nikke’s hit by these will suffer a permanent 5% ATK debuff.

Core

Yes, this thing has a core despite being very hard to see as it is really tiny, which means having a tiny hitbox too. It is located at the center of Gatekeeper. A MG or Sniper unit is needed as those weapons have very high accuracy, but other weapon users are able to hit core as well, just not very often.

Team Comps

Sword Squad (10k+ CS + Scarlet OL Ammo)

Roles

Liter = Attack buff, CDR

Viper= Breaking QTE circles (requires a 9k+ viper to comfortably break circles), DEF down and burst gen. Overload gear that has Elemental weakness rolls on her will greatly improve personal DPS as well.

2 Scarlets = Hahaha slicey damage big brrrt

Helm = Provides healing for mainly Scarlet since she self-inflicts damage, assists Viper to break QTE circles

This team aims to deal as much damage as possible with enough sustain to keep Scarlets alive. High CP is required. Helm is required to burst when her burst is available.

Core hitter gang (9k+ CS)

Roles

Liter = Attack buff, CDR

2 Modernia / 1 Modernia, 1 Scarlet= Hahaha Machine gun Brrrrt (Aim at the core)

Flex = Helm, or any other damage dealer if you are able to survive without healing. Maybe even another Modernia.

This team aims to hit core with Modernia as much as possible to maximize DPS, while also not be as punishing as running 2 scarlets in one team if RNG is not in your favor.

Hyper Scarlet (7-8k+ CS)

Roles

Liter = Attack buff, CDR

Guilty (can be replaced with Viper) = Guilty does really good damage against here, due to her ATK duplication and being a SG unit, she’s basically the best b2 damage dealer for this boss. The reason why Guilty is not placed in 10k cs+ team is because Helm alone will have a difficult time breaking circles unless hyper raised. Privaty can easily break circles by herself.

Scarlet = Hahaha slicey damage big brrrt

Helm = Scarlet/Guilty healing, assists Privaty to break QTE circles

Privaty = QTE circle breaker, sub DPS+buffer

This team aims for hybrid survivability and damage. Instead of worrying about 2 Scarlets dying, you only need to worry about 1. This team should work well at 7k-8k CP levels.

More team comps coming soon!
(Keep in mind that Modernia is kinda nerfed at this mode as co-op runs at 30 FPS which reduces MG DPS. The fire rate reduction also makes stacking her passive harder, resulting in even more DPS loss, however she can hit Gatekeepers core with ease and still do good damage).

Week 2 (Fire Weakness)

Modernia Reload team

Roles

Liter = Attack buff, CDR

Admi = Reload speed burst (level 5 is recommended at least)

Modernia = DPS , QTE breaker

Drake | Subs: Another Modernia, Very invested Alice= DPS QTE breaker

Privaty = ATK buffer + Reload speed (at least level 8 skill 1)

The goal of this team is to Ignore reload speed at 100% reload speed buff, this is especially useful for 2 Modernia teams as you basically skip her wind up time per reload, Survivability not needed if you leave one ring alive, drastically reducing boss DPS.