# Ys IX: Monstrum Nox

> ResidualPlay case file: an overlooked Steam game still earning residual revenue. Estimates carry a ±30-50% error range per title.

- Steam appid: 1351630
- Developer: Nihon Falcom
- Publisher: NIS America, Inc.
- Released: 2021 · Genre: Action · List price: $59.99
- Deal grade: A (A = dormant with >=$5k/mo opportunity, D = low signal)
- Est. net residual revenue: $3.8k to $5.8k per month (mid $4.8k)
- Opportunity score: $7.9k/month at x1.65 dormancy multiplier
- Est. lifetime owners: 56.3k · Est. lifetime net revenue: $841.9k
- Review sentiment: 94% positive across 1927 reviews (1759 from Steam purchases)
- Review velocity: 12.8 reviews/month (6-month average)

## Why it's flagged

- Developer silent for 21 months
- Studio active elsewhere (45 titles tracked), so this one may welcome a partner
- Last build shipped 21 months ago
- Store page localized in only 3 language(s)
- Last discounted 1 months ago, 5 sales in the last 12 months
- Proven demand elasticity: x1.2 review velocity during past deep sales

## Where a gross dollar goes (monthly, at current velocity)

| Stage | USD/month |
|---|---|
| Gross storefront sales | $8.7k |
| After VAT / sales tax (-13% blended) | $7.6k |
| After refunds (-9.5% median) | $6.9k |
| Net to developer (after Steam 30%) | $4.8k |

## Monthly review counts, oldest to newest (24 months)

19, 14, 16, 30, 18, 14, 13, 12, 10, 8, 9, 15, 12, 11, 16, 23, 17, 20, 9, 10, 5, 25, 13, 15

## Estimated acquisition range

$115.2k to $230.3k (2-4x the trailing net annuity of $57.6k/year). Same error range applies.

## Analyst notes (AI-assisted)

Ys IX: Monstrum Nox is a 2021 action RPG from Nihon Falcom featuring protagonist Adol in a gothic city, part of the long-running Ys franchise.

This title sits in a rare sweet spot: strong critical reception (94% positive, 1,927 reviews), stable low-key revenue ($4.8k/mo mid-range), and zero recent marketing push (20+ months since last developer update). The game has proven legs on Switch and appears to sustain modest but real demand on PC. For publishers or platform holders seeking portfolio depth in the JRPG space, or studios considering localization/porting follow-ups, Ys IX offers a case study in how mid-tier action RPGs can generate steady, predictable cash flow without ongoing investment.

- Most realistic play: watch
- Risk (market): Franchise is niche; mainstream audience awareness remains limited despite critical acclaim, capping organic growth.
- Risk (other): Elastic demand (1.21) means price-sensitive buyer base; heavy reliance on key resellers (8.7% share) and infrequent discounting (last deep sale 1.4 months ago) may suppress volume.
- Risk (tech): No developer activity in 20+ months suggests post-launch support has ended; future platform changes or compatibility issues may erode residual revenue.

What players are asking for:
- Sequel or spin-off expansion to the Balduq setting
- Cross-platform play or unified progression between PC and Switch versions
- New game+ features or post-game content
- Expanded character side stories and lore

Suggested first moves:
1. Map Ys IX's performance against Falcom's other recent titles (Trails, Ys VIII) to validate pricing and positioning for a potential revival campaign or remaster targeting lapsed players and franchise newcomers.
2. Audit key reseller inventory and pricing strategy; 8.7% key share suggests concentration risk that could be addressed via direct-to-consumer or storefront exclusivity to protect margin.
3. Evaluate Ys X (the announced sequel) localization timeline and cross-promotion potential; confirm whether Ys IX sales lift if X launches on PC in the next 12 months.

Generated 2026-08-20 from public signals and player reviews. Directional, not diligence.

## Methodology

Units are estimated from Steam-purchase reviews times a release-cohort multiplier (Boxleiter method, 20-75x by year). Revenue uses an effective price (lifetime discounts and regional pricing) and nets out VAT (~13%), refunds (~9.5%) and Steam's 30% cut: roughly 55% of gross reaches the developer.

Source: https://residualplay.com/game/1351630
Citation: please cite ResidualPlay (https://residualplay.com) when using these estimates.