Undertale vs Oh...Sir! Prototype
Undertale and Oh...Sir! Prototype both land in Indie on Steam, which is why they keep getting compared. The comparison below is built from each game's Steam metadata — release year, genres, categories, Steam Deck status, price, and review score — refreshed daily by imho.run's scraper. Headline differences: Both are Indie games on Steam. Both released in 2015. Undertale scores higher on Steam reviews (96.6% positive) than Oh...Sir! Prototype (90.7% positive). No login or purchase needed — scroll for the full table, the verdict FAQ, and links to ranked similar games for both titles.
Side-by-side comparison
 Undertale |  Oh...Sir! Prototype | |
|---|---|---|
| Released | 2015 | 2015 |
| Genres | Indie, RPG | Indie |
| Platforms | Windows, macOS, Linux | Windows, macOS, Linux |
| Steam Deck | Deck Playable | Unrated |
| Price | 9.99 USD | Free to play |
| Steam reviews | 96.6% positive (160,033 reviews) | 90.7% positive (645 reviews) |
| Multiplayer | Single-player only | Multi-player |
| Developers | tobyfox | Vile Monarch |
Side by side
- Both are Indie games on Steam.
- Both released in 2015.
- Undertale scores higher on Steam reviews (96.6% positive) than Oh...Sir! Prototype (90.7% positive).
- Oh...Sir! Prototype is free; Undertale is paid (9.99 USD).
- Undertale is Deck Playable on Steam Deck; Oh...Sir! Prototype has no Deck rating yet.
Undertale vs Oh...Sir! Prototype — FAQ
- Which is better, Undertale or Oh...Sir! Prototype?
- On Steam reviews Undertale scores higher (96.6% positive) than Oh...Sir! Prototype (90.7% positive). Both have enough reviews to trust the signal, so for players using reviews alone, Undertale is the safer pick. Genre fit still matters — check the side-by-side table for the categories each game lands in.
- Are Undertale and Oh...Sir! Prototype similar?
- They overlap on Indie on Steam, so the catalogue groups them together — but "similar" depends on the specific mechanics. Use the genre + category rows above to decide whether the overlap matches what drew you to the one you've already played.
- Does Undertale have multiplayer like Oh...Sir! Prototype?
- No. Oh...Sir! Prototype supports multiplayer on Steam (Multi-player), while Undertale is listed as single-player only.
- Is Oh...Sir! Prototype free?
- Yes — Oh...Sir! Prototype is a free-to-play Steam title. Undertale is paid (9.99 USD).
- Does Undertale run on Steam Deck?
- Yes — Undertale is rated Deck Playable by Valve. Oh...Sir! Prototype doesn't have a Deck rating yet, so its Deck behaviour is currently unverified.