Cthulhu Saves the World is done in the style of early-90s console RPGs such as Dragon Quest and the earlier Final Fantasy games, where the game interface shows either super-deformed ("chibi") sprites gallivanting across the world, or hordes of monsters arranged in a line in front of you when you encounter them. Game commands are given by a series of nested menus, all controlled by a mix of shift, enter, and arrow keys, occasionally leading to frustrating trips in and out of sub-menus (mostly when trying to juggle equipment). Combat is fully turn-based, so you have time to ponder your moves while the monsters stand there and bouncy music plays.

You begin alone, but you soon find Umi, a young girl with a starfish in her hair and a strong fetish for squid-headed gods of insanity. As you adventure together, you will battle endless hordes of monsters, complete quests, and acquire new companions, including a talking sword and a necromancer. Discovering the odd plot twists is part of the fun. As you kill monsters and perform quests, you begin to unlock many new abilities.

The storyline of Cthulhu Saves the World is very straightforward; you will never be overwhelmed by choices. Mostly, you fight your way from one area to another. The bulk of gameplay is spent in large maze-like zones--whether caverns, forests, temples, or alien spaceships--and you explore them, constantly running into random encounters. Each zone, fortunately, has an encounter limit...when you've reached that limit, the encounters stop, making exploration much easier.

There's a wide variety of monsters with strengths, weaknesses, and special powers, and a number of interesting bosses. The fights, especially against large random groups or the boss monsters, can be quite challenging, and tactics matter. The faster you defeat the monsters, the more magic points you regain, but using overwhelming force will cost you far more MP than you get back, and running out of MP usually means a trip back to town and an often tiring sequence of battles to get back to where you were (unless you've hit the encounter limit, in which case it's quite quick).

While each maze or zone has its own look, there's not a lot of variety within the area, in keeping with the limited graphics capacity of the old consoles. This can make large mazes, like the Ghost Forest, very tedious to go through--not to mention hard to navigate, as it's hard to remember which identical branching passage you've explored and which you haven't. On the other hand, the variety of monsters you will encounter in each zone is large, and the random mixes of monsters and their interacting powers make fights interesting. (Hint: If you encounter any monsters with the 'shielding' power, destroy them with extreme prejudice.)