Editing Rexouium (section)

== Open Species Ecosystem ==

As an officially declared '''open species''', the Rexouium design can be used by any creator to produce derivative bases, characters, accessories, and designs — with credit given to Ryker as the species' originator. This decision dramatically accelerated the spread of the species and led to a rich creator ecosystem.

=== Third-Party Avatar Bases ===

==== Rexouium Evolved & EvoRex HD — by Tosca ====

'''Tosca''' (also known as xTosca) created a fully from-scratch Rexouium-species model in their own distinct style, '''not using any assets from the original Rezillo Ryker base'''.

<blockquote>
"This is a brand new Rexouium model, not using any assets from the original, created in my own style."
<br/>— <i>Tosca, Gumroad listing</i>
</blockquote>

{| class="wikitable"
|-
! Product !! Release !! Key Features
|-
| '''Rexouium Evolved''' || 2021 || Digitigrade/plantigrade legs; full FBT; MMD visemes; Substance Painter files; Tosca's distinct art style
|-
| '''EvoRex HD''' || 2023 || Remaster of Evolved; split UVs for higher-resolution textures; two feather variations; free upgrade for Evolved owners; Quest-compatible planti version
|}

''Technical note: Tosca pioneered dynamic digitigrade legs on the Rexouium Evolved using a Unity bone constraint method originally developed by '''DragonSkyRunner'''. More recent versions use a method by '''Reign04'''. At the time of the original Evolved release, VRChat did not support constraints for Android builds, so the digi rig was PC-only.''

Commercial use of the EvoRex/EvoRex HD is unrestricted beyond the prohibition on redistributing model files themselves.

==== Rezuium — by Hirozu ====

The '''Rezuium''' (named as a portmanteau of "Rezillo" + "Rexouium") is a distinct Rexouium-species model created from scratch by '''Hirozu''', with explicit permission from Rezillo Ryker.

<blockquote>
"I was given permission by RezilloRyker to make this model and sell it."
<br/>— <i>Hirozu, Gumroad listing</i>
</blockquote>

{| class="wikitable"
|-
! Feature !! Details
|-
| '''Style''' || Distinct from both Ryker original and Tosca; Hirozu's own aesthetic
|-
| '''Face Tracking''' || Built-in; VRC Unity Face Tracking setup included
|-
| '''Clothing''' || Separate accessory/clothing package available
|-
| '''Distribution''' || Gumroad; public test version available in VRChat
|-
| '''Commercial ToS''' || Re-sale of the model itself prohibited; use as part of other content allowed with credit
|}

===== The HTC U24 Pro Commercial Incident =====

The Rezuium gained notable external visibility when it appeared in an '''HTC U24 Pro smartphone commercial'''. HTC initially published the commercial '''without crediting Hirozu''', constituting a breach of the Rezuium's terms of service. Following community pressure, HTC republished the commercial with the appropriate creator credit. This incident is documented as a significant moment in VRChat creator rights history — one of the first instances of a VRChat avatar base appearing in a major consumer electronics advertisement.

=== Notable Community Derivatives ===

Beyond full bases, the Rexouium's open species status has generated a wide variety of derivative works from the community:

* '''Rexouium Pooltoy''' (by Furriest & Taeliou Wolf) — pooltoy-aesthetic variant with inflation/deflation systems, Quest-compatible, Substance Painter files included
* Numerous texture commissions, custom accessories, clothing packs, and species crossbreeds documented across the VRChat creator community
* The species is frequently referenced in VRChat avatar worlds, custom texturing streams on TikTok and Twitch, and creator marketplaces