Games like Mystic Saga
Games like Mystic Saga include DAVE THE DIVER, There Is No Game: Wrong Dimension, That's not my Neighbor, Papers, Please, and Hidden Folks. We matched them by the tags players give Mystic Saga on Steam (Adventure, Casual, Simulation, Hidden Object, and Point & Click): closest matches first, and among equally close ones the better-known games.

DAVE THE DIVER
Shared: Casual · Adventure · Singleplayer

There Is No Game: Wrong Dimension
Shared: Adventure · Point & Click · Casual

That's not my Neighbor
Shared: Adventure · Casual · Point & Click

Papers, Please
Shared: Simulation · Point & Click · Singleplayer

Hidden Folks
Shared: Casual · Hidden Object · Point & Click

The Sims™ 4
Shared: Simulation · Free to Play · Singleplayer

The Room
Shared: Adventure · Point & Click · Singleplayer

Where Winds Meet
Shared: Singleplayer · Free to Play · Adventure

Varenje
Shared: Adventure · Casual · Free to Play

House Flipper
Shared: Simulation · Singleplayer · Casual

Train Simulator Classic
Shared: Simulation · Singleplayer · Casual

My Brother Rabbit
Shared: Adventure · Point & Click · Singleplayer

Lost and Found Co.
Shared: Hidden Object · Point & Click · Adventure

Unpacking
Shared: Casual · Simulation · Relaxing

Disney Dreamlight Valley
Shared: Adventure · Simulation · Casual

Potion Craft: Alchemist Simulator
Shared: Simulation · Singleplayer · Casual

Morphopolis
Shared: Hidden Object · Casual · Adventure

Game Dev Tycoon
Shared: Simulation · Casual · Singleplayer

Organized Inside
Shared: Casual · Simulation · Hidden Object

Hero of the Kingdom
Shared: Adventure · Casual · Point & Click

The Room 4: Old Sins
Shared: Adventure · Point & Click · Hidden Object

Slime Rancher 2
Shared: Singleplayer · Adventure · Simulation

When The Past Was Around
Shared: Hidden Object · 2D · Singleplayer

Enigmatis: The Ghosts of Maple Creek
Shared: Adventure · Hidden Object · Casual