The basic Melee enemy type is the most common obstacle the player faces throughout the game. It chases the player and attempts to hit them with a punch if within range. Although not particularly threatening on its own, its presence can often act as a nuisance once combined with other specialized enemy types.

When I started working on it, the Melee enemy had fairly common inconsistencies with sensing the player and successfully attacking them with its strike. After resolving these issues, I ended up using this enemy type as the base to develop additional universal enemy behaviors upon. An example of these behaviors is the "starting patrol behavior". This allowed level designers to specify a sequence of movements for enemies to perform on spawn before returning to standard behavior.

The Projectile enemy type, unlike its red counterpart, remains stationary. However, after a brief windup, it quickly launches a large metal ball that can damage the player. While this enemy can be a challenge to fight depending on how far away it is, its attacks can also be used to the player's advantage. The metal balls deal significant damage to other enemies, so leading other targets into the projectile's trajectory can quickly dispatch otherwise troublesome foes.

In updating this enemy type, I fixed several small bugs that had negatively affected gameplay. For example, the enemy’s projectiles would initially linger in the level after being fired and obstruct the player, so I gave the balls a maximum travel distance and corresponding self-destruction logic. Gameplay issues also frequently arose from the enemy’s lack of any long-range attack telegraphs. I worked with my team's VFX artist to design and implement an aiming beam effect that filled this absence. 

The Defender enemy poses a challenge for players due its passive effect: the ability to create impassable electric walls between other nearby Defenders. When used in large enough groups, entire damaging nets and fences can be created.

Out of the three basic enemy types, I spent the most amount of time working on features and fixes for the Defender. One such feature was an ambient patrolling behavior. Defenders could be given a specified patrol route to follow, allowing their wall obstacles to dynamically shift. This increased the potential for new and interesting level design opportunities.

I faced a large challenge in working on the Defender to resolve complicated issues involving the generation and removal of the electric barriers. In its initial state, barriers would often:

• Not generate between sufficiently close Defenders

• Not update their positions to match their two associated Defenders

• Persist beyond the destruction of one or both of their associated Defenders

• Possess colliders that wouldn't match the position and orientation of their VFX indicators 

Trying to resolve these issues and simplify the system at large proved to be a challenge due to a lack of documentation. By methodically analyzing and testing the previous system's individual components, I was able to engineer a new system that achieved the effects I desired.

For this enemy, the team was interested in a design that played around the game's central battery mechanic. We came up with an enemy that could steal one of the player's dropped batteries, and the "Gremlin" terminology stuck shortly thereafter. 

In standard idle gameplay, Gremlins act in a completely passive manner, wandering around their current area at random intervals. Once a battery was dropped, Gremlins would directly try to move towards it, placing it on their backs and out of the player's reach if it was successfully stolen. 

Iterations and additions to the Gremlin frequently modified what they would do after a battery was capable of being stolen. Initially, the Gremlin would merely stand in-place upon pickup, waiting for the player to approach and destroy them. Efforts to make the Gremlin somewhat of a greater threat caused this "stand-in-place" behavior to be changed. In its final version, the Gremlin generates an area-of-effect healing ability if standing nearby other normal enemies. If there isn't anybody to heal, the Gremlin tries to run away from the player. If a given encounter has multiple Gremlin enemies in it, Gremlins that aren't carrying a battery try to protect the carrying Gremlin by swarming around them.

One of the designs I suggested within the initial brainstorming meeting was the Barrier enemy, which aims a directional shield towards the player to block projectiles. This idea was meant to be another iteration on the "enemy via obstruction" concept already explored through the basic "Defender" enemy type. To differentiate it further from the Defender, it was decided that the Barrier enemy's shield would also reflect incoming projectiles rather than just negate the damage from them. As such, this was used as a highly effective means to protect other enemies.

In order to strike a fair balance between being tricky to defeat and too obnoxious to deal with, two inherent limitations of the Barrier enemy's shield were baked into its design. We wanted to enable players of any ability loadout to be able to combat this enemy. Therefore, the Barrier enemy both stands in place and has a very limited rotational speed, meaning that careful positioning and quick damage output could lead to a rapid victory. Furthermore, by only being effective against directed projectile abilities, the enemy is highly susceptible to area-of-effect attacks and long-reaching melee attacks.

The concept of the Pulse enemy, an agent that would periodically generate a momentary outward force in an outward radius, was another iteration on the "enemy via obstruction" concept. Not only could these pulses protect it from a player attacking at close range, but they could also meaningfully disrupt the player while tackling other challenges. By messing with the player's positioning, the pulses make it harder for the player to quickly clear combat encounters, avoid stage hazards, and retrieve dropped battery backs. For all of these reasons, this enemy type was reserved for encounter augmentation roles within the game's later levels. 

• The Melee Miniboss has significant upgrades to its movement and attack speeds. 

• The Projectile Miniboss fires a larger projectile, making it more difficult to outmaneuver their attacks. 

• The Miniboss Defender has a unique wave respawning mechanic, which periodically creates four new standard Defenders to form a protective ring around itself. 

• The Miniboss Gremlin has a unique short-range attack that they can use to directly steal the battery from the player. 

• The Pulse Miniboss generates a larger outward force, causing disruption within a significantly larger area-of-effect. 

• The Barrier Miniboss surrounds itself with four large barriers, making positioning and projectile ability use more difficult.