Across the Obelisk is a cooperative deck-building rogue-lite with RPG mechanics that players can either play solo or with their friends. You will need to unlock cards, create your own deck and face powerful opponents during your adventure. As you progress through the game, you will need allies to help you during quests and one such ally is Gustav.
This guide will tell you how to unlock Gustav in the game.
How To Unlock Gustav in Across the Obelisk
Completing the quest required to unlock Gustav is pretty easy but it takes up a lot of time since you need to travel to 3 different maps.

First, you need to complete Act 1 and then head toward the green portal on the map.
In this portal, you need to go to the Lonely Rock node and pass through the South Pier node first.

Make sure that you have atleast 800 gold to purchase a boat and reach there. You can select the [Bargain] option to open a skill check but if you fail then you won’t be able to use the boat and will need to start a new game since combat is not an option here.
Therefore it’s recommended that you choose to [Buy] the boat as it is a much safer option and will ensure that you can travel further on the map.

Once you reach the Lonely Rock node, select the [Accept] option to help Gustav and get him the Flute that he wants.

Now complete Act 2 and then head over to the blue portal on the map.
Once you reach the blue portal, you will need to visit the Mansion node on the map.

There are quite a few dialogue choices in this quest and you need to select the [Continue] option to go toward the left wing and take the flute for Gustav.

You will receive an Honourable Boom as a reward along with 150 gold and 20 Shards.

Gustav will now be unlocked and you can add him to your team.
That’s it, now go ahead and follow these steps to unlock Gustav!