How to Make an Atomic Bomb in Your Garden Collab Events Guide

What Are Collab Events in the Garden?

Collab events are limited-time crossovers where your backyard nuclear project gets a twist. These events introduce exclusive storylines, rare components, and special visitor mechanics. Unlike the standard game loop of fundraising and part hunting, collab events often feature unique characters or items from other indie titles, adding a layer of unpredictability to your already dangerous hobby.

Each event typically lasts one to two weeks. During this window, you can access event-specific missions that reward you with parts that cannot be obtained through normal gameplay. These parts are often required for achieving the highest-yield atomic devices or unlocking secret endings. The events also introduce temporary NPCs, such as suspicious "repairmen" or "census takers," who are actually agents from the collaborating universe.

To participate, you must have progressed past the initial tutorial phase, which is roughly the first hour of gameplay. The event icon appears on your workbench interface once available. Missing an event means those exclusive parts may return only during a future rerun, so staying informed is key.

Current and Upcoming Collab Events

As of the game's launch on June 9, 2026, the developers at karahan have announced a roadmap of collab events. The first major crossover is scheduled for late June, featuring the game My Summer Car. This event introduces a new "engine block" component that can be repurposed as a radiation shield. Players must assemble a makeshift vehicle to transport the block without alerting the police.

Another confirmed event is a partnership with Papers, Please in August. During this event, your mailbox will receive forged documents that allow you to order restricted chemicals. However, you must correctly inspect each document at your kitchen table mini-game, or the delivery will be intercepted by federal agents. Successfully passing inspection adds a significant boost to your bomb's yield.

A third event, rumored but not yet confirmed, involves The Final Station. This would introduce a "mysterious passenger" who hides in your shed and provides alien alloy in exchange for food and secrecy. The official Steam page for How to Make an Atomic Bomb in Your Garden will be updated with event dates as they are announced.

How to Prepare for a Collab Event

Preparation is crucial for maximizing your event rewards. Before an event begins, ensure you have at least 500 in-game currency saved. Many event missions require upfront investment to bribe informants or purchase fake permits. Additionally, stockpile basic materials like scrap metal and wiring, as event recipes often demand more resources than standard builds.

Your relationship with neighbors also matters. Events frequently involve increased scrutiny from NPCs. If your neighbor suspicion meter is high, they will report strange deliveries to the authorities, causing event items to be confiscated. Use the "friendly chat" interaction daily in the week leading up to an event to lower their alertness.

Lastly, review the beginner guide for stealth fundamentals. Events often have tighter time limits, so knowing how to quickly hide your workbench or distract agents is essential. Consider upgrading your shed's lock system from the upgrades guide before the event starts.

Event-Exclusive Rewards and Their Uses

Collab events are the primary source for "unique core" components. These cores have special properties that affect your atomic bomb's final classification. For example, the My Summer Car event offers the "Satsuma Core," which increases blast radius by 15% but adds a loud engine noise that attracts attention during the final assembly phase.

The Papers, Please event rewards a "Stamp of Approval" cosmetic for your bomb casing, which reduces suspicion from mail carriers. This is purely cosmetic but can be combined with other items for a hidden achievement. More importantly, completing all event missions unlocks the "Diplomat's Briefcase" storage upgrade, doubling your inventory space for event-specific items.

Some rewards are consumable, such as "Instant Coffee" from a potential Coffee Talk crossover, which temporarily boosts your crafting speed by 30%. These items cannot be crafted normally, making them valuable for speedrunning the main campaign. Refer to the achievements guide for a complete list of event-related trophies.

Avoiding Detection During Events

Events significantly increase the patrol frequency of federal agents. In standard gameplay, you might see one agent per week. During an event, expect daily drive-bys and occasional door-to-door "surveys." The key is to maintain a low profile. Never work on your bomb during daylight hours when event NPCs are active. Always use the night cycle for crafting.

The event-specific "Noise Meter" is a new mechanic. Each event action, like using power tools or testing circuits, generates noise. If the meter fills, a special event agent arrives and confiscates your latest event item. To manage this, spread your work across multiple in-game days. Use the resource management guide to plan your material usage efficiently.

If an agent questions you, choose dialogue options that express confusion or innocence. Aggressive responses trigger a search warrant, ending the event prematurely for your current playthrough. Patience is your greatest tool; rushing through event objectives is the fastest way to get caught.

1. Stockpile Resources

   Gather at least 500 currency and basic materials before the event starts.

2. Lower Neighbor Suspicion

   Use friendly interactions daily for one week prior to the event.

3. Work at Night

   Only craft event items during the night cycle to avoid patrols.

4. Complete Missions Early

   Finish event missions within the first three days to avoid the final patrol spike.

Frequently Asked Questions About Collab Events

Can I replay past collab events? No, events are time-limited. However, karahan has mentioned potential "rerun archives" in a future update. For now, missing an event means waiting for a rerun or trading with other players via the unofficial community market.

Do collab events affect the main story? They can. Some events introduce permanent NPCs or locations if you complete specific objectives. For instance, finishing the My Summer Car event adds a broken car to your driveway that serves as a permanent hiding spot. Check the endings guide for details on how events influence final outcomes.

Are there any free-to-play limitations? Since the base game is paid, all event content is included with your purchase. There are no microtransactions for event access. However, you must own the base game on Steam to participate.

How do I know when a new event starts? The game displays a notification on the main menu. You can also follow the developer's announcements on the Steam community hub. The patch notes guide will be updated with event start dates and patch details.