Image
AI Emoji Generator on Martini
Slack admin at a 200-person company building a 20-emoji custom pack for the workspace — happy mascot, party mascot, deadline-stress mascot — and every reaction needs to descend from one consistent character. Drop the mascot reference once, fan across Flux, Nano Banana 2, Midjourney, GPT Image 2, and Seedream for expression variations, output as 128x128 PNGs ready for Slack admin upload.
What this feature solves
Custom emoji are how a workplace community develops its voice. The Slack admin at a 200-person fintech wants 20 reaction emoji that match the brand mood — a custom mascot smiling, a custom mascot crying laughing, a custom mascot sweating about a deadline, a custom mascot celebrating a launch. Off-the-shelf Slack emoji from public packs are generic; the in-house design team is busy with the actual product. The admin needs to produce a coherent set without hiring a designer for what is essentially a culture investment.
The other half is character consistency across the set. A 20-emoji pack with 20 inconsistent mascot faces breaks the joke — every emoji should obviously be the same character in a different mood. Tab-based AI image tools generate one image per session and force the admin to manually re-prompt the mascot description into every new generation. By emoji number 12, the mascot has drifted on color, on outfit, on face proportions, and the pack reads as a stack of unrelated cartoons rather than a cohesive set.
And there is the format and platform layer. Slack wants 128x128 PNG, file size under 128KB. Discord wants 128x128 minimum, animated emoji as APNG or GIF for boost-tier servers. Custom brand emoji for an internal style guide want vector or high-resolution masters. Generic AI image generators do not produce platform-specced output and do not separate the mascot reference from the per-emoji emotion prompt — the chain that produces a clean pack is exactly what tab-based tools cannot express.
Why Martini is different
Martini anchors the mascot once on the canvas. Drop the mascot reference image as a single labeled image node — the brand mascot, the team in-joke character, the executive caricature the team approves. Every per-emoji emotion prompt (smiling, party-popper, crying-laughing, sweat-drop) wires into the same anchor. The 20-emoji pack becomes a fan-out from one upstream character node, and every reaction descends from the same source character — the visual identity holds across the whole pack automatically.
Multi-model fanout for expression variety. Flux delivers high-fidelity character renders. Nano Banana 2 handles mascot detail and reference fidelity at small sizes (which is what 128x128 emoji need). Midjourney brings stylistic range for the more illustrative reactions. GPT Image 2 refines the strongest expressions. Seedream offers tasteful editorial variation. The chain runs all five from the same mascot anchor and the admin picks the strongest expression-by-expression — without re-uploading the mascot reference 20 times.
Downstream chaining handles platform formats. Once each emoji lands, chain into a 128x128 export pass for Slack and Discord, into an animated APNG variant for Discord boost tiers (using the lip-sync or frame-extraction tool node patterns when an animated reaction makes sense), and into a transparent-background cutout via the background-removal tool. The admin uploads the finished pack through Slack workspace settings or Discord server settings — Martini does not auto-publish to either, but the canvas produces the file bundle ready for the admin's upload flow.
Common use cases
Brand mascot reaction pack for a Slack workspace
Anchor the company mascot once and fan out 20 reaction emoji — happy, sad, party, sweat, eye-roll, applause — for company-wide use.
Discord community pack for a game guild or fan server
Game community generates themed emoji that match the server lore — boss reactions, victory cheers, gear drops — all from one character anchor.
Executive caricature emoji set for an internal team
With explicit consent from each exec, generate caricature reaction emoji for an inside-joke set the leadership team uses in all-hands threads.
Brand emotion library for an internal style guide
Marketing team produces a brand-aligned emoji library — 30 expressions of one mascot — for use in newsletters, blog posts, and customer comms.
Holiday or launch-themed emoji drops
Halloween mascot, holiday mascot, launch-day mascot — the same character in seasonal variations across a coherent annual pack.
In-joke reaction emoji for a small team Discord
A 10-person startup builds private custom emoji that capture team in-jokes and culture moments without hiring a designer.
Recommended model stack
flux
imageHigh-fidelity character renders that hold detail at small emoji sizes.
nano-banana-2
imageMascot reference fidelity that keeps the same character across every emotion variant.
midjourney
imageStylistic range for illustrative and exaggerated emoji reactions.
gpt-image-2
imageEdit-aware refinement to clean expression details before final export.
seedream
imageEditorial variation when the brand wants a more illustrative emoji direction.
How the workflow works in Martini
- 1
1. Anchor the mascot reference once
Drop one clean reference image of the brand mascot as a labeled image node. Every emoji in the pack inherits from this single source.
- 2
2. List the 20 reactions as text prompts
Write out the emotion list — smiling, party-popper, crying-laughing, sweat-drop, applause, eye-roll, surprised, sleepy, salute, fire, prayer, thumbs-up, deadline-stress, victory, mind-blown, suspicious, love-eyes, vacation, snack, weekend.
- 3
3. Fan out across Flux, Nano Banana 2, Midjourney for the first three reactions
Run the smiling, party, and crying-laughing variants in parallel across all three models from the same mascot anchor. Compare takes; lock the winning model for the rest of the pack.
- 4
4. Run the remaining reactions through the locked model
Lock the strongest model (often Nano Banana 2 for mascot fidelity) and run the remaining 17 emotion prompts through it from the same anchor. The pack stays consistent.
- 5
5. Refine the strongest expressions through GPT Image 2
For the showcase reactions (party-popper, victory, mind-blown), pipe through GPT Image 2 for edit-aware cleanup of expression details before export.
- 6
6. Chain into background-removal and 128x128 export
Wire each finished emoji into the background-removal tool for transparent backgrounds, then resize to 128x128 PNG (Slack spec) and 256x256 (Discord spec). The chain produces ready-to-upload files.
- 7
7. Hand off to the workspace admin for upload
Bundle the 20-emoji pack and hand to the Slack admin or Discord moderator. Upload happens through the platform's own settings flow — Martini produces the files; the admin handles platform publishing.
Example workflow
Diego is the Slack admin at a 200-person fintech and the team wants a custom emoji pack featuring the company mascot — a friendly otter named Coco. The brand team has a single Coco illustration approved for marketing. Diego opens a workspace canvas, drops the Coco reference as the upstream mascot anchor, and lists 20 reactions in a text node — smiling, party, crying-laughing, sweat-drop, deadline-stress, victory, sleepy, salute, fire, prayer, thumbs-up, mind-blown, suspicious, love-eyes, vacation, snack, weekend, applause, eye-roll, surprised. He runs the first three reactions in parallel across Flux, Nano Banana 2, and Midjourney; Nano Banana 2 holds Coco's character best at small size. He locks Nano Banana 2 for the remaining 17 reactions. Each generated emoji chains through GPT Image 2 for expression cleanup, then through background-removal for transparency, then into a 128x128 PNG export. The 20-emoji pack lands in a single canvas. Diego uploads through Slack workspace settings; the team starts using Coco-stress and Coco-party in deadline threads within the hour.
Tips and common mistakes
Tips
- Anchor the mascot once. The whole pack reads as one character only when the upstream reference stays locked.
- Use Nano Banana 2 as the locked model for mascot fidelity at small sizes. The 128x128 export is unforgiving; Nano Banana 2 holds detail.
- Fan out only on the first few reactions for model selection. Running 20 emoji across five models is wasteful — pick the winner once, then scale.
- Slack has a 128KB file size cap per emoji. Run the export through compression if the PNG comes out too large.
- Save the canvas as the company emoji template. Holiday and seasonal drops next year inherit from the same Coco anchor.
Common mistakes
- Using a copyrighted character as the mascot. Pikachu, Mario, Marvel, Disney — all off-limits for emoji packs that ship to a workspace, even an internal one.
- Generating real-person emoji without explicit consent. Caricatures of real colleagues need permission; caricatures of public figures invite likeness-rights problems.
- Letting the mascot drift across the pack. Without a single locked anchor, emoji 17 looks like a different character than emoji 1.
- Promising auto-publish to Slack or Discord. Martini produces the files; the admin uploads through the platform's own settings flow. The platforms also have content guidelines (no profanity, hate, impersonation) the admin should check before upload.
- Ignoring file-size constraints. Slack caps custom emoji at 128KB; Discord at varying sizes per server boost tier. Compress before upload.
Related how-to guides
Related models and tools
Tool
AI Background Removal
Remove backgrounds from images for assets and compositing on Martini.
Tool
AI Image Upscaling
Upscale images and keyframes before final video generation on Martini.
Provider
Google's Veo video, Imagen image, and Nano Banana model workflows on Martini.
Provider
OpenAI
OpenAI's GPT Image and Sora video model workflows available on Martini.
Provider
ByteDance
ByteDance's Seedance video and Seedream image model families on Martini.
Related features
AI Sticker Generator — Telegram, WhatsApp, Discord Packs
Generate sticker packs for Telegram, WhatsApp, Discord, and iMessage on Martini.
AI Icon Generator — App and UI Icons on Martini
Generate app icons, UI icons, and brand icon sets on Martini's canvas.
AI Character Design — Game and Story Characters on Martini
Design original characters for games, stories, and animations on Martini's canvas.
AI Style Transfer — Apply Artistic Styles to Images on Martini
Transfer artistic styles between images using AI on Martini.
AI Character Consistency Across Images and Video
Keep a subject consistent across image and video generations on Martini using reference workflows.
AI Character Reference — Reference-Image Workflows on Martini
Use reference images to guide AI model outputs on Martini's canvas.
AI Photo Restoration — Restore Old Photos on Martini
Restore old, damaged, or low-quality photos with AI on Martini's canvas.
AI Product Photography — Studio-Quality Product Images on Martini
Generate studio-quality product photos for e-commerce on Martini's canvas.
AI Headshot Generator — Professional Headshots in Minutes
Generate professional headshots for LinkedIn, resumes, and team pages on Martini's canvas.
AI Mockup Generator — Product, Device, and Brand Mockups
Generate product, device, and brand mockups for marketing on Martini's canvas.
AI Thumbnail Generator — YouTube and Social Thumbnails
Generate scroll-stopping thumbnails for YouTube, podcasts, and social on Martini.
AI Logo Generator — Brand Marks and Wordmarks on Martini
Generate logo concepts, brand marks, and wordmarks on Martini's canvas.
AI Comic Strip Generator — Multi-Panel Comics on Martini
Generate multi-panel comic strips with consistent characters on Martini's canvas.
AI Presentation Slides — Pitch Decks and Slide Visuals
Generate slide visuals, pitch deck imagery, and presentation graphics on Martini.
AI Architecture Rendering — Building and Space Visualization
Generate architectural renderings, exterior visualizations, and concept art on Martini.
AI Interior Design — Room and Space Visualization on Martini
Visualize interior designs, room concepts, and decor schemes on Martini's canvas.
AI Game Asset Generator — Sprites, Concept Art, Backgrounds
Generate game-ready assets, sprites, concept art, and backgrounds on Martini.
Related docs
Related reading
Comparisons
Frequently asked questions
Can I upload AI emoji directly to Slack or Discord?
Martini produces the files (128x128 PNG for Slack, 256x256 PNG or APNG for Discord). The actual upload happens through the workspace admin settings on each platform — Martini does not auto-publish. Both platforms have content guidelines (no profanity, hate, impersonation) the admin should review before publishing the pack.
Is using a copyrighted character as my mascot okay?
No. Generating Pikachu, Marvel, Disney, or any registered character as a custom emoji is a likeness and copyright violation, even for internal workspace use. Build emoji packs around your own brand mascot, original characters, or fully licensed IP. AI image models will happily produce copyrighted characters, but using them is on you.
How do I keep all 20 emoji looking like the same character?
Anchor the mascot reference image once on the canvas as the upstream node. Every per-emoji emotion prompt wires into the same anchor; the model receives the mascot as the consistent visual source and the emotion as the per-emoji variable. Use Nano Banana 2 as the locked model — it holds character fidelity at small sizes better than peers.
Which model is best for emoji?
For mascot fidelity across a 20-emoji pack, Nano Banana 2 leads — small-size character detail holds better than the alternatives. Flux is a strong second for high-detail reactions. Midjourney brings illustrative range for stylized variants. GPT Image 2 handles edit-aware refinement on showcase emoji. Seedream offers editorial variation for brand emoji libraries.
Can I generate emoji of real people on my team?
Only with the explicit consent of each person depicted. Caricatures of teammates for an internal in-joke pack need documented permission; caricatures of public figures, customers, or competitors are likeness-rights territory and a clear ethical line.
What about animated emoji for Discord boost servers?
Discord supports APNG or GIF animated emoji on boost-tier servers. The canvas can produce frame variations of the same expression and chain into an animated export, but for full-motion mascot animation, the dedicated lip-sync and video tooling on Martini is a better fit. Most workspace emoji packs ship as static PNGs first; animated variants follow as a second pass.
Build it on the canvas
Open Martini and wire this workflow up in minutes. Free to start — no card required.