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: every newcomer has to verify with the bot before they can write, while existing members keep chatting as usual. The threshold grows with the size of the group, storm mode lifts itself after a set time, and the owner gets an alert. 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 the same verification to every newcomer, 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 every newcomer has to verify with the bot in a private chat before they can write, so scripted accounts are filtered out before they can post. Existing members are not affected and keep chatting as usual.
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 newcomers have to verify. The aim is to sit comfortably above your normal join rate so ordinary growth never trips the alarm — and for larger groups the shield raises the threshold automatically.
- Join threshold: default 10 and never lower; larger groups automatically get a higher one — one join per minute for every 200 members.
- Detection window: default 60 seconds, range 5 to 3600.
- Storm mode duration: default 15 minutes, range 1 to 1440.
- The threshold never goes below 10 and already grows with the member count, so large active groups rarely need to raise it by hand — do it only if your normal peaks are higher still.
- 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: keep the minimum of 10 over 60 seconds — against such a quiet baseline even a modest coordinated push stands out.
- Active public group with steady growth: start from the default of 10 over 60 seconds — for larger groups the shield raises it automatically — and go higher only if legitimate bursts still 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 switches storm mode on.
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 storm mode with /raidon, 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.
- Keep newcomer verification on for 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 alarms and makes every newcomer verify for no reason.
- Setting it too high for a quiet group, so a real raid slips under the trigger.
- Switching newcomer verification off for storm mode: without it the automatic shield does not switch on at all and sends no alerts — you can still turn verification on manually with /raidon.
- Turning owner alerts off, then being surprised later by spam a raid left behind.