Top mods / Bosses of Mass Destruction
Not listed
Bosses of Mass Destruction doesn't list Minecraft 26.3 on Modrinth. The newest release it lists is 1.21.1, on Fabric (beta files only).
Open Bosses of Mass Destruction on Modrinth
This is what the mod's author listed on Modrinth, not a test. A listing doesn't prove a mod runs on your setup, and a missing listing doesn't prove it fails. Versions must match exactly, and files published elsewhere, such as CurseForge, aren't counted.