R.A.I.L.S.
R.A.I.L.S. is an isometric tower defense built around a core constraint: turrets can only be placed on movable rail networks.
This system transforms tower defense from static optimization into dynamic spatial planning, where players must constantly reposition defenses instead of relying on fixed placements.
Project Overview
As team lead, I coordinated the design direction of the project and maintained communication between departments
As systems designer, I was responsible for designing the core rail-based placement system, defining turret behaviors and enemy archetypes.
​Project Details​
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Role: Team lead & System designer
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Team: 16 developers (design, programming, concept art, 3D art)
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Genre: Isometric tower defense
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Engine: Unity
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Production Time: 8 months
Team Leadership
Managing a multidisciplinary team required balancing design direction, production constraints, and communication between departments.
My main responsibilities included:
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Defining the core gameplay vision and maintaining consistency across features.
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Coordinating design decisions with programming and art departments.
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Supervising playtesting sessions and analyzing player feedback.
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Maintaining design documentation and system specifications
One key example was aligning design decisions with programming constraints, often simplifying mechanics or prioritizing features to keep the project achievable within our development timeframe.
Each department had a representative, and I worked closely with them to ensure the design remained technically feasible while preserving the intended player experience.
This role required splitting my time between system design work and team coordination, ensuring the project progressed toward a cohesive gameplay vision.
Cover art for the game - not my work
Brief showcase of the game
Core System: Rail-Based Turret Placement
Traditional tower defense games allow players to place static defenses in optimal locations.
In R.A.I.L.S., every turret must be placed on a rail network, forcing players to constantly reposition defenses depending on enemy paths.​
This system creates three design consequences:
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Spatial planning - players must plan out efficient rail layouts before placing turrets.
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Dynamic defenses - repositioning turrets becomes part of the strategy.
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Resource efficiency - resources used without a solid plan might become wasted.
Design
Goals of the project
The design focused on creating a system that encouraged players to interact continuously with the defense layout rather than relying on passive optimization.
Key goals included:
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Creating a strategic sandbox where players could experiment with rail layouts.
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Starting with simple mechanics and gradually increasing system complexity.
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Encouraging active player participation during enemy waves.
Systems I designed
Turret system
I designed and iterated on the behavior and progression of the game's turrets, defining:​
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Attack patterns.
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Targeting behaviors.
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Upgrade roles within the defensive system.
The goal was to ensure each turret served a distinct tactical purpose within the rail-based placement system.
Enemy archetypes
To support the core mechanic, I designed enemy types that required players to adapt turret positioning and rail layouts:
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Increased durability.
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Unpredictable movement.
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Pressure on specific areas of the defense network.
Full gameplay video
These enemies encouraged players to actively reposition turrets instead of relying on fixed defenses.
Challenges and solutions
Challenge - Encouraging players to use the rail system
One of the main challenges was ensuring players actually engaged with the rail mechanic instead of attempting traditional tower defense strategies.
Early versions allowed players to use a single shared resource to build both rails and turrets.
During playtesting we observed that players often:
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invested heavily in rails while neglecting turrets
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or ignored rails entirely and built static defenses.
Solution
To address this, I redesigned the economy so that rails and turrets used separate resources.​
This encouraged players to experiment with rail layouts while still maintaining strong defensive capabilities.
Collaboration with programming
The programming team faced significant workload constraints during development.
To keep the project achievable, I worked closely with them to prioritize the most important gameplay features, focusing development around the rail system and core combat loop.
This collaboration allowed us to deliver a functional and cohesive gameplay experience despite production limitations.
Playtesting and feedback
I supervised the project's playtesting sessions and analyzed player feedback.
Observing players interact with the rail system provided valuable insights into how the mechanic was interpreted in practice.
This feedback guided several adjustments to:
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the resource system
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turret accessibility
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pacing of enemy waves
Intro of the game with VO - I worked on the script
These iterations helped reinforce the intended gameplay loop of designing and adapting a dynamic defense network.
Lessons Learned
Working on R.A.I.L.S. reinforced the importance of observing how players interact with systems in practice.
Even when mechanics appear logically sound during design, players often approach them in unexpected ways.
This project taught me to:
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validate design assumptions through playtesting
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simplify systems to highlight the core mechanic
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adapt design decisions to technical and production constraints
This project also showed me how easily players revert to familiar strategies. Even when a system introduces a new mechanic, players will often attempt to play it like the genre they already know.
These lessons helped me develop a stronger approach to system iteration and collaborative development.