Over roughly 7 days we ran a set of Reddit ad campaigns, spending about $1,200, to find which creatives, subreddits, and audiences convert. The whole loop (creative generation, campaign setup, and analysis) runs on Claude Code.
Cost per install roughly halved as we cut losers and concentrated on what converts.
Validated learnings
On audience, creative formats, content, and platform. Detail below.
AI-assisted process
We used AI to: 1. Generate 100+ ad creatives 2. Run campaigns via the Reddit API 3. Build auto-reinforcing learning loops
We are not claiming the best formula yet. We have started finding heat and are improving each iteration, with the numbers to show it.
Result · the trend
CPI is trending down, roughly 2× lower.
We ran daily iterations as learnings compounded, producing an ongoing improvement trend (dashed trend line).
CPI ($/install) Installs/day A · B · C = iterations · 6/21 = forecast
*6/21 was a partial day. Forecast assumes a full day (~$150 spend) converting at our best-day rates, implying ~$15 CPI and ~10 installs. Actuals still accruing.
Result · where we're headed
Each optimization step takes another bite out of CPI.
Focusing on our winners already leads to <$15 CPIs. We expect to drive CPI <$10 with a new wave of creatives and AI-driven learning loops.
A wide mix of creatives across static, video, AI, and manual.
A sample of what we tested: characters, memes, before/after art, streamer reactions, lasers, bombs, and video. Some bombed, some found heat.
u/ChessArena · Promoted
you think you're downloading chess. you're not.
u/ChessArena · Promoted
this is the queen in our chess game. her name is Kindra.
u/ChessArena · Promoted
this is the queen in our chess game. her name is Kindra.
u/ChessArena · Promoted
this is the king in our chess game. his name is Legion.
u/ChessArena · Promoted
chess players can't agree if this battle royale counts as chess
u/ChessArena · Promoted
Chess with no turns
🔇 video
u/ChessArena · Promoted
if chess had a fever dream
🔇 AI video
u/ChessArena · Promoted
if chess had a fever dream
u/ChessArena · Promoted
we put lasers in chess. we're not sorry.
u/ChessArena · Promoted
chess, but your king drops bombs.
u/ChessArena · Promoted
streamers keep rage-quitting our chess game. (it has no turns.)
u/ChessArena · Promoted
we redid our game's art style.
Learning 01 · Audience
The game is most marketable to chess and auto-battler players.
We read cost at the ad-set level (CPI, de-duplicated). The subreddit view shows where audiences engage, on CTR and CPC. (A per-subreddit CPI would mislead: Reddit double-counts each install across every sub the person saw.)
Conv counts overlap (Reddit credits one install to every sub the person saw).
CHESS DOMINATES
Every chess sub engages and converts. Creator communities (r/gothamchess) lead, at 1.27% CTR and $0.44 clicks.
Auto-battler (TFT/autochess) also converts. We don't fully know why yet; our hypothesis is that auto-battler players already see their game as a kind of chess.
Why chess works: the game reads clearly as chess, but feels novel and exciting to people who already love it.
GAMING TARGETING FAILS
Zero installs on ~$120 of MOBA (LoL, dota2), plus more on broad gaming.
Engagement is ~10× worse: MOBA 0.07-0.09% CTR vs chess ~0.8%, and clicks cost 4-5× more ($2.65-3.01 vs ~$0.60).
Why: to video gamers chess looks intimidating or strange and our gameplay does not translate. This is also why our non-gameplay creatives convert best (next slides).
Learning 02 · Video format
Reddit needs its own video format.
How we optimized our videos for Reddit.
Ported our Shorts
Reused our portrait YouTube Shorts on Reddit as-is, built around a sound-on hook.
Barely anyone watched
~7% play rate, zero installs. Most people never even started the video.
Learning
Portrait is not Reddit-native (tiny on desktop), and autoplay is MUTED, so the spoken hook is lost.
Recut for Reddit
Landscape with on-screen captions. Play rate jumped to 52-66% and produced every video install.
BEFORE · portrait Short, ported from YouTube
🔇 MUTED on Reddit
7% play rate · 0 installs. Portrait renders tiny on desktop and barely autoplays. With no sound, the spoken hook is lost.
AFTER · landscape recut with captions
captions carry the hook
52-66% play rate. Plays in-feed; captions carry the hook with sound off.
Learning 03 · Static → video
Our best static creative became our best-playing video.
We used our strongest static concept as the brief for an AI-generated video. Winning statics are a cheap, proven source for video.
r/chess · Promoted · u/ChessArena
if chess had a fever dream
The static 0.76% CTR, our highest static
→
r/chess · Promoted · u/ChessArena
if chess had a fever dream
The video 66% play rate, our best
PLAY RATE BY VIDEO TYPE
Fever video (this static)
66%
Landscape recuts
52%
Long-form trailer
37%
Portrait Shorts
7%
THE PROCESS
Take the proven static's concept and hook, generate the video with AI (image-to-video), then recut landscape with captions. Static testing de-risks every video before we make it. Right now this is about a 1-day turnaround.
Learning 04 · Characters sell
Characters are unexpectedly the most efficient ad creatives.
Character-identity ads (Kindra the Queen, Legion the King) convert about 30% cheaper than our average image, and account for roughly half of all installs. That surprised us: a character roster is usually assumed to be table-stakes in F2P games, not a conversion hook.
r/chess · Promoted
V1
this is the queen in our chess game. her name is Kindra.
Kindra, original $19.15 CPI · 9 installs
r/chess · Promoted
V2
this is the queen in our chess game. her name is Kindra.
Kindra, sexier variant $13.64 CPI · 5 installs
r/chess · Promoted
V2
this is the king in our chess game. his name is Legion.
Legion, new character $15.57 CPI · 3 installs
Characters vs. the field
Character concepts avg ~$16.90 CPI vs $23.64 for the average image, and $35.77 for our highest-CTR "curiosity" creative (fever).
The iteration flow
V1 was a single Kindra. V2 added a sexier Kindra variant and a new character, Legion the King. Build out the cast as a marketing asset.
HYPOTHESIS
Why we think this works: (1) people and characters sell; (2) these are our two strongest characters, the sexy queen and the ominous king; (3) people are struck by the novelty of a chess game with characters. The mystery is a better draw than confusing or literal gameplay ads.
Learning 05 · Placement
Feed and comments are different mediums.
Feed drives the volume. Comments is a separate, higher-context lane that needs its own creative.
34
FEED installs
1
COMMENTS install
Feed drove 34 of 35 installs. Comments produced 1, at a high ~$68 CPI. But comments is a different medium, and the right creative moves it (below).
FEED · drives volume
r/chess · Promoted
this is the queen in our chess game. her name is Kindra.
ok this chess battle royale is unreasonably addictive and i don't fully understand why
Play Nowchessarena.gg
Join the conversation
HYPOTHESIS People in a thread are reading, not browsing, so they are not in a "discover something new" mindset. The opportunity is to sound like another poster in the thread, which relies far more on the copy than the image or video.
Where we go next
Next steps and opportunities.
NEAR-TERM
Concentrate spend on the two proven audiences (chess, auto-battler) and the winning creatives; cut the low performers.
Scale up. 35 installs is below Reddit's ~50+ threshold to optimize, and the core audiences (~3M chess, ~0.7M auto-battler members) are barely tapped. More volume should lower CPI on its own.
Build a lookalike audience based on installs once we hit 100+.
CREATIVE ENGINE
Allocate more spend to winning videos (landscape, captions), and fund the under-spent gameplay-first cut.
Make more videos inspired by our best static ads.
Incorporate characters more prominently in our marketing.
Develop comment-section native creatives.
AUDIENCE
Grow auto-battler spend, partner with auto-battler content creators, and make creatives written for that audience.
Target beginners with "new to chess, a new kind of chess" messaging.
Pursue a GothamChess (Levy) partnership, our cheapest creator audience.
STRUCTURAL (longer-term CPI levers)
Get on Steam. A trusted store should cut the friction between click and install.
Build a mobile-playable path. ~70% of Reddit inventory is mobile, but our PC-only funnel can't capture it.
Close the cross-device attribution gap so optimization runs on clean signal.
AGENTIC IMPROVEMENT LOOP
The setup. We now have baseline data, a creative engine, and a methodology.
The move. Hand AI a goal ("reach $X CPI through ad iteration") and let it run user acquisition agentically.
Why AI wins here. It can generate hundreds of creatives and hundreds of precisely-targeted ad sets, then analyze them, far faster than a human could set up.
Our role. Build the infrastructure, monitor the learning, enforce a hypothesis structure, and inject fresh creative ideas.
Chess Arena · Paid UA · prepared for board review · June 2026 · draft for layout review (final in Gamma)
