Portfolio: Karol Rzepa
Unity Developer
Turning ideas into fast, polished 2D and 3D mobile games in Unity. I turn coffee into rock-solid logic, smooth performance, and bug-free gameplay. Basically, I make sure the game plays as good as it looks.
Projects: 12
2026
Oil Inc.
Oil Inc. is our first commercial project published on Google Play and the first one to generate revenue. The goal of the project was to develop a complex mobile economic game, which provided hands-on experience in designing intricate idle systems, process automation, game state management, and optimization for mobile devices. Oil Inc. is an idle tycoon simulation game where the player builds and expands their own oil empire from scratch, managing a growing network of extraction, transportation, and resource sales. The gameplay revolves around purchasing new islands, building and upgrading oil pumps to improve efficiency and reliability, and managing limited space by clearing terrain obstacles. Players must balance storage tank capacities and upgrade a fleet of transport ships that automatically deliver oil to the main city for sale. The game combines passive income mechanics with continuous technological progression, requiring players to make strategic investment decisions to optimize their profits and accelerate growth.
Oil Inc.
Project Description
Oil Inc. is our first commercial project published on Google Play and the first one to generate revenue. The goal of the project was to develop a complex mobile economic game, which provided hands-on experience in designing intricate idle systems, process automation, game state management, and optimization for mobile devices. Oil Inc. is an idle tycoon simulation game where the player builds and expands their own oil empire from scratch, managing a growing network of extraction, transportation, and resource sales. The gameplay revolves around purchasing new islands, building and upgrading oil pumps to improve efficiency and reliability, and managing limited space by clearing terrain obstacles. Players must balance storage tank capacities and upgrade a fleet of transport ships that automatically deliver oil to the main city for sale. The game combines passive income mechanics with continuous technological progression, requiring players to make strategic investment decisions to optimize their profits and accelerate growth.
Team Members
- Karol Rzepa - Programmer
- Krzysztof Stolc - 2D Graphic designer
Screenshots
2026
Plunder Cards
Plunder Cards is a web-based tactical roguelike deckbuilder where players step into the boots of a pirate captain to assemble a formidable crew and defeat the legendary Kraken. Developed to gain hands-on experience in implementing turn-based card logic, dynamic game state management, and procedural map generation, the project focuses on core deckbuilding mechanics and strategic risk management. Players begin each run with a foundational deck of three cards, immediately drafting a fourth random card to define their starting strategy. The gameplay revolves around navigating a procedurally generated map, making key tactical decisions at random map nodes, and carefully curating their deck by acquiring new crew cards or purging weak ones. With fully randomized encounters, escalating difficulty after every victory, and permadeath mechanics, each run presents a unique challenge that requires precise planning and adaptability to reach the final boss.
Plunder Cards
Project Description
Plunder Cards is a web-based tactical roguelike deckbuilder where players step into the boots of a pirate captain to assemble a formidable crew and defeat the legendary Kraken. Developed to gain hands-on experience in implementing turn-based card logic, dynamic game state management, and procedural map generation, the project focuses on core deckbuilding mechanics and strategic risk management. Players begin each run with a foundational deck of three cards, immediately drafting a fourth random card to define their starting strategy. The gameplay revolves around navigating a procedurally generated map, making key tactical decisions at random map nodes, and carefully curating their deck by acquiring new crew cards or purging weak ones. With fully randomized encounters, escalating difficulty after every victory, and permadeath mechanics, each run presents a unique challenge that requires precise planning and adaptability to reach the final boss.
Team Members
- Karol Rzepa - Programmer
- Krzysztof Stolc - 2D Graphic designer
Screenshots
2026
Merito Runner
The goal of this project was to develop our first game in the Unreal Engine as part of a final assignment for Merito University, with a strong focus on practical learning of the environment (viewports, Blueprints, and user interface). The project enabled testing key systems, including collision detection, object spawning, and seamless scene transitions, establishing a solid foundation for further learning. Merito Runner is a fast-paced 2D-3D endless runner where the player competes to set a high score. The core gameplay centers on breaking distance records by avoiding various obstacles using jump and slide mechanics. Players must also collect coins, which are aided by a magnet power-up. Merito Runner features multiple character options and a visual style with a city skyline backdrop, including buildings in the background.
Merito Runner
Project Description
The goal of this project was to develop our first game in the Unreal Engine as part of a final assignment for Merito University, with a strong focus on practical learning of the environment (viewports, Blueprints, and user interface). The project enabled testing key systems, including collision detection, object spawning, and seamless scene transitions, establishing a solid foundation for further learning. Merito Runner is a fast-paced 2D-3D endless runner where the player competes to set a high score. The core gameplay centers on breaking distance records by avoiding various obstacles using jump and slide mechanics. Players must also collect coins, which are aided by a magnet power-up. Merito Runner features multiple character options and a visual style with a city skyline backdrop, including buildings in the background.
Team Members
- Karol Rzepa - Programming, Unreal Engine Development, Documentation, Design, Testing
- Kacper K. - Programming, Unreal Engine Development, Design, Testing
- Amadeusz B. - 3D Modeling, Design, Testing
- Kaj S. - Graphic Design, Audio
- Michał W. - Design, Documentation, Testing
Screenshots
2025
Twin Office Escape
Twin Office Escape is a 3D escape room game set in a university building inspired by Merito University in Gdynia, known in the game as Twin Office. The player is trapped inside the building, which serves as a large, interconnected puzzle. To escape, the player must explore the environment, collect items and solve puzzles and minigames. During the game, tasks include finding a screwdriver, repairing the electrical system by replacing a cable and activating fuses, obtaining a keycard, discovering a cipher and entering the correct code to unlock the exit. The gameplay is based on logical problem solving and gradually unlocking new stages of the game.
Twin Office Escape
Project Description
Twin Office Escape is a 3D escape room game set in a university building inspired by Merito University in Gdynia, known in the game as Twin Office. The player is trapped inside the building, which serves as a large, interconnected puzzle. To escape, the player must explore the environment, collect items and solve puzzles and minigames. During the game, tasks include finding a screwdriver, repairing the electrical system by replacing a cable and activating fuses, obtaining a keycard, discovering a cipher and entering the correct code to unlock the exit. The gameplay is based on logical problem solving and gradually unlocking new stages of the game.
Team Members
- Karol Rzepa - Programming, Unity Level Design, 3D Modeling, Documentation, Design, Testing
- Kacper K. - Programming, Audio, Design, Testing
- Amadeusz B. - Unity Level Design, Design, Testing
- Kaj S. - 3D Modeling, Design, Testing
- Michał W. - Design, Documentation, Testing
Screenshots
2025
Arveleen
Arveleen is a non-linear narrative Visual Novel developed in Ren’Py where the player takes on the role of a newly crowned monarch ruling during a time of crisis. The kingdom of Arveleen is on the brink of bankruptcy and its borders are threatened by an invasion from the fanatical Ca’z Empire. The game combines classic visual novel storytelling with resource management mechanics. Players must balance between two powerful religious factions, the Cult of Fire and the Cult of Nature or choose a neutral path focused on engineering and trade. Each decision affects the kingdom’s stats, relations with neighboring states and the tactical options available in the final stage of the game.
Arveleen
Project Description
Arveleen is a non-linear narrative Visual Novel developed in Ren’Py where the player takes on the role of a newly crowned monarch ruling during a time of crisis. The kingdom of Arveleen is on the brink of bankruptcy and its borders are threatened by an invasion from the fanatical Ca’z Empire. The game combines classic visual novel storytelling with resource management mechanics. Players must balance between two powerful religious factions, the Cult of Fire and the Cult of Nature or choose a neutral path focused on engineering and trade. Each decision affects the kingdom’s stats, relations with neighboring states and the tactical options available in the final stage of the game.
Team Members
- Karol Rzepa - Programming, Graphics, Storyline
- Kacper K. - Programming, Graphics, Storyline
Screenshots
2024
Harrim
Harrim is a 2D Multiplayer Tug-of-War strategy game where the objective is to destroy the enemy’s base. The project was an early attempt at building a more complex Unity game, including both a singleplayer campaign and a multiplayer mode. Players create and upgrade units, gain experience and unlock improvements as they progress. The game also features a profile system that saves player progress, wins and match history. Development provided experience in animation, gameplay logic and multiplayer integration using Photon Classic.
Harrim
Project Description
Harrim is a 2D Multiplayer Tug-of-War strategy game where the objective is to destroy the enemy’s base. The project was an early attempt at building a more complex Unity game, including both a singleplayer campaign and a multiplayer mode. Players create and upgrade units, gain experience and unlock improvements as they progress. The game also features a profile system that saves player progress, wins and match history. Development provided experience in animation, gameplay logic and multiplayer integration using Photon Classic.
Team Members
- Karol Rzepa - Programmer
- Krzysztof Stolc - 2D Graphic designer
Screenshots
2024
Monkey Circus
Monkey Circus is an Arena Horde Survival game created during HackJam 2024 in Gdańsk. The game was developed in two days, providing experience in rapid prototyping, working with Tilemaps and 2D NavMesh, and creating scripts for pixel art, enemy movement and collisions. The player takes on the role of a clown in a circus full of monkeys - some attack up close while others throw bananas. The goal is to survive as long as possible, with the game automatically tracking survival time and defeated enemies. Players must rely on dexterity, reflexes and strategic obstacle avoidance to succeed.
Monkey Circus
Project Description
Monkey Circus is an Arena Horde Survival game created during HackJam 2024 in Gdańsk. The game was developed in two days, providing experience in rapid prototyping, working with Tilemaps and 2D NavMesh, and creating scripts for pixel art, enemy movement and collisions. The player takes on the role of a clown in a circus full of monkeys - some attack up close while others throw bananas. The goal is to survive as long as possible, with the game automatically tracking survival time and defeated enemies. Players must rely on dexterity, reflexes and strategic obstacle avoidance to succeed.
Team Members
- Karol Rzepa - Programmer
- Krzysztof Stolc - 2D Graphic designer
Screenshots
2023
Jumping Hats
Jumping Hats is an educational 2D arcade side-scroller. The goal was to develop a complete mobile game in Unity that combines simple, skill-based gameplay with progression and a reward system. The player controls a jumping hat, earning points by passing obstacles and collecting coins that increase the score multiplier. Coins can be exchanged for new hats in the shop. The game also features achievements, a daily reward chest system, Unity Ads integration, and a dynamically generated map that becomes increasingly challenging as the player progresses.
Jumping Hats
Project Description
Jumping Hats is an educational 2D arcade side-scroller. The goal was to develop a complete mobile game in Unity that combines simple, skill-based gameplay with progression and a reward system. The player controls a jumping hat, earning points by passing obstacles and collecting coins that increase the score multiplier. Coins can be exchanged for new hats in the shop. The game also features achievements, a daily reward chest system, Unity Ads integration, and a dynamically generated map that becomes increasingly challenging as the player progresses.
Team Members
- Karol Rzepa - Programmer
- Krzysztof Stolc - 2D Graphic designer
Screenshots
2023
Tenebryss
This project was created for educational purposes to learn and experiment with Pygame. Tenebryss is a 2D turn-based game in Python using Pygame. The player competes against an AI opponent to collect coins on a randomly generated map, uncovering terrain shrouded in a fog of war. The first to collect 6 coins wins.
Tenebryss
Project Description
This project was created for educational purposes to learn and experiment with Pygame. Tenebryss is a 2D turn-based game in Python using Pygame. The player competes against an AI opponent to collect coins on a randomly generated map, uncovering terrain shrouded in a fog of war. The first to collect 6 coins wins.
Team Members
- Karol Rzepa - Creator
Screenshots
2022
Doubloons
Doubloons is an educational project created for a Game Jam. The game allowed learning teamwork in Unity, scripting and function creation, object hierarchy management, and inventory system implementation, as well as gaining experience with WebGL publishing. Players control a cat exploring locations to find items and coins, which can be exchanged for other resources. The goal is to marry the Queen of Cats, with the additional challenge of completing the game in as few turns as possible. The game features a map, turn counter, inventory, combining exploration, item collection, and strategic planning.
Doubloons
Project Description
Doubloons is an educational project created for a Game Jam. The game allowed learning teamwork in Unity, scripting and function creation, object hierarchy management, and inventory system implementation, as well as gaining experience with WebGL publishing. Players control a cat exploring locations to find items and coins, which can be exchanged for other resources. The goal is to marry the Queen of Cats, with the additional challenge of completing the game in as few turns as possible. The game features a map, turn counter, inventory, combining exploration, item collection, and strategic planning.
Team Members
- Karol Rzepa - Programmer
- Krzysztof Stolc - 2D Graphic designer
Screenshots
2021
Green Cube
This was my first 3D game and first Android project, created for educational purposes to deepen my knowledge of C# and practical Unity development. The project included UI handling, animations, asset and font management, game state saving, as well as basic 3D mechanics such as object physics and enemy AI. Green Cube is a 3D arcade puzzle game where the player controls a green cube, avoiding obstacles, collecting coins, and moving objects. Players need both logical thinking and dexterity to complete the five prepared levels.
Green Cube
Project Description
This was my first 3D game and first Android project, created for educational purposes to deepen my knowledge of C# and practical Unity development. The project included UI handling, animations, asset and font management, game state saving, as well as basic 3D mechanics such as object physics and enemy AI. Green Cube is a 3D arcade puzzle game where the player controls a green cube, avoiding obstacles, collecting coins, and moving objects. Players need both logical thinking and dexterity to complete the five prepared levels.
Team Members
- Karol Rzepa - Creator
Screenshots
2019
Kebabo
This project was created for educational purposes, focusing on practical use of Unity, mastering C#, UI handling, asset and font management, and implementing game state saving and loading. Kebabo is a clicker/tycoon game built in Unity. The player starts with a small food truck and completes orders to earn money. The earnings can be reinvested into larger locations, farms that generate passive income, and offices that boost overall profits. The main goal of the game is to grow the business and unlock all achievements.
Kebabo
Project Description
This project was created for educational purposes, focusing on practical use of Unity, mastering C#, UI handling, asset and font management, and implementing game state saving and loading. Kebabo is a clicker/tycoon game built in Unity. The player starts with a small food truck and completes orders to earn money. The earnings can be reinvested into larger locations, farms that generate passive income, and offices that boost overall profits. The main goal of the game is to grow the business and unlock all achievements.
Team Members
- Karol Rzepa - Creator
Screenshots
