У вашего броузера проблема в совместимости с HTML5
Blind playthrough of "First Offensive" (foff.bsp), a custom Q2 single player map made by Dirk Diggler.
Release Date: 17/03/1998
Download (foff.zip):
http://www.3dgamersedge.com/spq2lvlrevs/firstoffensive.html
Skill 2 Hard
Secrets = 3/4
Kills = 111/112
Game: Quake 2
https://store.steampowered.com/app/2320/QUAKE_II/
Custom Engine: Q2XP 1.26.8 final release (by Quake2XP Team)
https://www.moddb.com/mods/quake-2-xp/
HD Weapons Models: Quake 2 Weapons Remodel (by Turic)
https://www.moddb.com/mods/quake2-remodel
HD Monster skins: Quake 2 Monster Skins (by Fragger)
https://www.moddb.com/mods/quake-2-monster-skins
HD HUD and HD Menu are from KMQuake2
http://www.markshan.com/knightmare/
Soundtrack: Q2N64
https://aubreyhodges.bandcamp.com/album/quake-2-nintendo-64-official-soundtrack