Games like Days of Doom
Games like Days of Doom include The Last Spell, Darkest Dungeon® II, Mewgenics, Jagged Alliance 3, and Into the Breach. We matched them by the tags players give Days of Doom on Steam (Tactical RPG, Turn-Based Tactics, Roguelite, Perma Death, and Strategy): closest matches first, and among equally close ones the better-known games.

The Last Spell
Shared: Turn-Based Tactics · Strategy · Turn-Based Strategy

Darkest Dungeon® II
Shared: Turn-Based Tactics · Roguelite · Perma Death

Mewgenics
Shared: Turn-Based Tactics · Roguelite · Turn-Based Strategy

Jagged Alliance 3
Shared: Turn-Based Tactics · Strategy · Tactical RPG

Into the Breach
Shared: Strategy · Turn-Based Tactics · Turn-Based Strategy

Legends of Kingdom Rush
Shared: Turn-Based Tactics · Tactical RPG · Turn-Based Strategy

The Dungeon Beneath
Shared: Turn-Based Tactics · Tactical RPG · Roguelite

XCOM 2
Shared: Strategy · Turn-Based Tactics · Singleplayer

Lost Eidolons: Veil of the Witch
Shared: Turn-Based Tactics · Roguelite · Tactical RPG

Invisible, Inc.
Shared: Turn-Based Tactics · Tactical RPG · Strategy

Inkbound
Shared: Tactical RPG · Turn-Based Tactics · Roguelite

Trials of Fire
Shared: Turn-Based Tactics · Tactical RPG · Roguelite

XCOM®: Chimera Squad
Shared: Turn-Based Tactics · Strategy · Turn-Based Strategy

Warriors of the Nile
Shared: Strategy · Roguelite · Turn-Based Tactics

FTL: Faster Than Light
Shared: Strategy · Roguelike · Perma Death

LONESTAR
Shared: Turn-Based Tactics · Strategy · Roguelike

STAR WARS Zero Company™
Shared: Turn-Based Tactics · Turn-Based Strategy · Strategy

Crown Trick
Shared: Roguelite · Roguelike · Perma Death

King Arthur: Knight's Tale
Shared: Tactical RPG · Turn-Based Tactics · Roguelite

Monster Train
Shared: Roguelite · Turn-Based Tactics · Turn-Based Strategy

Peglin
Shared: Roguelite · Roguelike · Strategy

Fell Seal: Arbiter's Mark
Shared: Turn-Based Tactics · Strategy · Tactical RPG

Templar Battleforce
Shared: Tactical RPG · Turn-Based Tactics · Perma Death

Hard West 2
Shared: Turn-Based Tactics · Turn-Based Strategy · Tactical RPG