The anti-raid shield watches for sudden surges of joins. When too many people join within a short window, it switches on storm mode automatically, locking down the group and optionally requiring a captcha, then lifts it after a set time and alerts the owner. It reacts in seconds, day or night, so a coordinated flood never catches you offline.
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Open in your dashboard1How it detects a raid
A raid is a coordinated flood of accounts joining at once to spam or disrupt a group. The shield counts how many members join within a rolling time window and compares that number to your threshold.
If the count crosses the threshold inside the window, storm mode switches on immediately, with no manual action needed even at 3am. The watch runs continuously, so it catches a burst the moment it starts rather than after the damage is done.
2Why automatic reaction matters
Raids are timed to hit when moderators are least likely to be watching, often overnight or during a holiday. By the time a human notices dozens of accounts flooding the chat, hundreds of spam messages may already be posted.
The shield removes the human bottleneck. It reacts in seconds and applies a consistent lockdown, so the outcome of a raid does not depend on whether someone happened to be at their keyboard. When it is over, the group returns to normal on its own.
3What storm mode does
During storm mode the group goes into lockdown and newcomers are handled far more strictly. You can also require a captcha from everyone joining while the raid is active, so scripted accounts are filtered out before they can post.
Storm mode stays on for the duration you set, then lifts automatically and the group returns to normal. Legitimate members who join during a raid are not punished; they are simply asked to verify.
4Tuning the thresholds
Three numbers control sensitivity: the join threshold, how many joins trigger it; the detection window, over how many seconds those joins are counted; and the storm mode duration, how long the lockdown lasts. The aim is to sit comfortably above your normal join rate so ordinary growth never trips the alarm.
- Join threshold: default 20, range 3 to 500.
- Detection window: default 60 seconds, range 5 to 3600.
- Storm mode duration: default 10 minutes, range 1 to 720.
- Smaller, quieter groups should lower the threshold; large active groups should raise it to avoid false alarms.
- If a promo or shout-out sometimes brings a legitimate burst of joins, set the threshold above that expected peak.
5Tuning by group type
The right numbers depend entirely on how fast your group normally grows. Start from these and adjust after watching real join patterns.
- Small private community, a few joins a day: threshold around 5 to 8 over 60 seconds catches even a modest coordinated push.
- Active public group with steady growth: keep the default of 20 over 60 seconds and raise it only if legitimate bursts trip it.
- Large channel-linked chat with frequent spikes: threshold of 50 or more, and a longer window, to avoid false alarms on organic surges.
- Group that gets periodic promo-driven joins: set the threshold above your typical promo peak so real traffic never triggers a lockdown.
6Owner alerts
When a raid is detected, the bot can send the owner a direct message so you know it happened and can review the aftermath. This is on by default and is your cue to check the moderation journal for anything that slipped through.
Even though storm mode acts on its own, the alert keeps you in the loop so you can decide whether to extend the lockdown, tighten thresholds, or ban specific accounts that got in.
7Best practices
The shield is most reliable when its thresholds match reality and it is backed by the other newcomer layers.
- Set the threshold just above your busiest normal minute so genuine growth never triggers it.
- Enable captcha during storm mode so raiders are filtered even in the middle of a flood.
- Keep owner alerts on so you are never surprised by a raid you slept through.
- Pair the shield with new member restrictions and content moderation so accounts that do get in still cannot spam freely.
8Common mistakes
Most anti-raid problems come from thresholds that do not match the group's real behaviour.
- Setting the threshold too low for an active group, which turns normal growth into constant false lockdowns.
- Setting it too high for a quiet group, so a real raid slips under the trigger.
- Leaving captcha off during storm mode, which lets scripted accounts post even while locked down.
- Turning owner alerts off, then being surprised later by spam a raid left behind.