Individual Student Project - Twin-stick Shooter Boss Battle


The main goal of this individual student project was to design and prototype a slice of fun and intense gameplay in a top-down, twin-stick-shooter, sci-fi boss encounter.

The primary mechanic which the gameplay is centered around is the player's ability to use a shield which fills a dual purpose:

  • it protects the player from incoming enemy shots,

  • it absorbs the enemy shots to build up a charge which can be used for a powerful Charge Shot.

This mechanic was in part inspired by the classic shoot-em-up game Ikaruga, which I played a lot on the Nintendo GameCube when I was younger.

Boss Features

    The boss has three main attacks:

    • Rapid Fire volleys of fast-moving yellow shots, alternating between sweeping from inside out to outside in.

    • Cluster Bombs, slow-moving red shots which split into smaller ricocheting fragments.

    • EMP Bombs, slow-moving but homing blue bombs which cause a large electrical explosion, disabling the player and draining any built-up shield charge.

    There is also a Shield Generator Phase, where the boss spawns three shield generators.

    Until all three are destroyed, the boss is invulnerable and will be frantically shooting yellow shots in random directions. The Shield Generator Phase happens twice during the fight.

    Game Juice

    I focused on creating a good game feel with clear and "juicy" feedback to the player, such as:

    • Clear feedback when damaging enemies, with enemies flashing red when they take damage.

    • Clear indication of the player taking damage, with screen shake and a full-screen red flash.

    • Various particle effects when enemy shots hit the player and the arena walls, and electric buzzing indicating when the player is stunned.

    • Animated UI elements clearly indicating damage taken, change in shield charge levels, shield cooldown, and button prompts highlighting when the shield and the charge shot can be used.

    • Satisfying death sequence for the boss, as well as a charming intro sequence.


    This project was created using Unreal Engine 4 with the use of some free asset packs for models and particle effects, and scripted entirely with Blueprints. Here's an example of how the Blueprints look.

    As you can see I value clear structure and well commented code - something I learned the value of through all my years of working as a programmer - which both simplifies my own workflow and also makes it much easier for someone else to read, understand, and potentially take over and continue on my work.

    The Challenge of the OP Shield

    The biggest challenge of the game design was to balance the shield mechanic so that it didn't become overpowered, and that the player would just keep the shield active at all times. To make the shield more costly and risky to use, and to incentivize more strategic use of the shield...

    • The player moves much slower while the shield is active.

    • When the shield charge is full the shield will overload and kill the player unless the charge shot is fired within a couple of seconds.

    • The shield is put on a cooldown after the Charge Shot is fired.

    • The boss periodically fires a homing EMP bomb which stuns the player and drains the shield charge. While the player's shield is active, the player moves slower than the boss' EMP bomb, forcing the player to deactivate the shield to be able to avoid the EMP.

    Boss Attack #1: Rapid Fire

    The boss has three main attacks, which are clearly color-coded so as to be easily distinguishable.

    The first is a double-barrel, rapid-fire, sweeping volley of fast-moving yellow shots, aimed so that the sweeps are centered on the player's current position.

    This attack alternates between sweeping from the outside and inwards, and from the inside and outwards.

    Boss Attack #2: Cluster Bombs

    The second is a volley of four red slow-moving Cluster Bombs which detonate mid-flight, each splitting up into six smaller red shots which spread out in all directions.

    These smaller shots are also slow-moving, but will each bounce once on the surrounding walls, covering the arena in a chaos of small bullets.

    Boss Attack #3: EMP

    A blue homing EMP bomb which explodes after a set time (so as not to follow the player indefinitely). If hit by the EMP or caught in its explosion, the player will become stunned for a moment, unable to shoot, move or use the shield, and any shield charge will be depleted. If the player is moving when hit by the EMP, they will keep moving slowly, unable to steer.

    The boss will randomly switch between these three attacks, with two limitations:

    • the boss will never repeat the same type of attack twice in a row,

    • a cluster bomb attack is always followed by an EMP attack.

    This forces the player to keep moving to avoid the EMP instead of standing still in a safe corner while the arena is full of cluster fragments, and this also avoids the potentially unfair situation of the arena being full to the brim with both red and yellow shots at the same time.

    The Shield Generator Phase

    When the boss has lost a third of its health, three shield generators will spawn out of the floor and the boss will become shielded and invincible until all three generators are destroyed.

    During this phase the boss will rapidly and endlessly fire yellow shots in random directions, forcing the player to always keep moving.

    After the generators are destroyed the boss will return to its three main attacks, and when the boss has lost two thirds of its health, this shield phase will trigger once again with three new shield generators.

    The Only Way To Heal

    When each shield generator is destroyed, it will leave a single small health pack which the player can pick up to restore a health amount corresponding to a single bullet hit.

    This gives the player a limited ability to restore some health only at certain points of the boss encounter, creating tension and anticipation as well as promoting careful and strategic play.

    Reflections and Improvements

    There is no ramping up of difficulty during the boss' phases, meaning the challenge is the same at the beginning and near the end. A few ideas for how the gameplay could get more challenging after each Shield Generator phase:

    • The arena could get smaller.
    • The Cluster Bombs could split into more fragments.
    • The Rapid Fire volleys could get wider and include more shots.
    • The EMP could move faster.
    • Each Shield Generator phase could include increasing numbers of generators.

    The player's shield can currently be slightly exploited, since the shield can remain active during the overload phase, with no limit on the number of absorbed shots in the meantime, however forcing the shield to deactivate when full could possibly be deadly to the point of being unfair.

    The charge shot could be more impactful and satisfying to use, e.g. by clearing away nearby enemy shots when fired, and having more particle trails for the shot itself.