Undertale was developed by Toby Fox and officially released for PC (Windows/macOS/Linux), PlayStation 4, PlayStation Vita, Nintendo Switch, and Xbox One. Sony never published Undertale for the PlayStation Portable (PSP).

Below is a draft post you can use for a forum, blog, or social media community like Reddit's r/PSP .

Undertale was originally developed using . While this engine supports modern consoles, it does not natively export to the legacy PSP hardware. Official releases are limited to: PC/Linux/macOS (2015-2016) PlayStation 4 & PS Vita (2017) Nintendo Switch (2018) Xbox One (2021) 2. The Homebrew Scene and Unofficial Ports

for the Sony PlayStation Portable (PSP). The game was never officially ported to this handheld, and any "hot download" links for a full Undertale ISO for the PSP are likely misleading or contain incomplete homebrew projects.

To address your request, it is important to first clarify that there is of

However, the dedicated homebrew community has developed several fan-made "demakes" and ports. If you are looking to play a version of

Let me stop you right there. As someone who has bricked a PSP-1000, lost a memory stick to a virus, and spent three days trying to patch a corrupted EBOOT, I need to give you a reality check—and then point you toward the actual truth.