Traverse dimensions, slay fell beasts, kill yourself trying to rocket jump. Quake shouldn't need an introduction I'll get straight to it. Quakespasm-Spiked is the best quake source port out there and I'll stand by that. The world of Quake ports is split between orthodox, mostly vanilla-compatible deathmatch clients, and largely singleplayer clients that break limits, and have excellent scripting and mapping support. QSS does both. You can play the biggest, most heavily modded maps in multiplayer with the best Quake networking I've seen. Proper headless server support means you can find SQuakeT at sqt.computer:2600
You need the orignal quake data files to play, as well as the Arcane Dimensions mod. You can find them here. Included: Entire GOG Quake: The Offering filesets, with Quake and its expansions' data, the windows dosbox and dosbox configs for vanilla, Linux and OpenBSD AMD64 builds of Quakespasm-Spiked, and the arcane dimensions mod data in /ad/. Command line parameters for Quakespasm-Spiked are mostly the same as Quakespasm. Run with '-game ad' to play arcane dimensions.