Horizon Breakout (Zombies)

Gameplay Non-critical kills = 200 points. Critical/Melee kills = 300 points. Every 100 points of healing to your teammates = 100 points. Use points to purchase more areas in the map or new heroes to play. If an ally dies, you can revive them by standing in the circle left at the position they died. The time it takes to revive a teammate increases with each revive, and resets each round.

Enemies Enemies scale in strength, health, and speed with each player, as well as the round number. Enemies have a chance to drop powerups, which include 3x Points, Increased Speed, Increased Damage, Unlimited Ultimate, a Passive Heal, a Freezing Zone around each player, an Overshield, and Endless Ammo.

Challenge Rounds Every 5th round is a "Dragonfall Round" where Hanzo fires dragons from up in Shimada Castle. Other rounds have a chance to be one of 7 other challenge rounds. They modify the round and make it more, well.. challenging! In exchange you are rewarded with points that scale up with the Round number. The 7 possible challenge rounds are as follows:

Levitation Rounds - Players and enemies levitate for a few seconds upon taking damage.
Team Up Rounds - Players take extra damage when they are separated from their teammates.
Volatile Air Rounds - Players and enemies take damage over time if they are in the air at any time.
Ghost Rounds - Enemies rotate between being visible and invisible for seconds at a time.
Juggernaut Rounds - One enemy gains a lot of health and a little more damage for the entire round.
Self Destruct Rounds - Every enemy explodes upon death, dealing damage to nearby players.
Tiny Shimadas Rounds - All enemies are scaled down in size for the duration of the round.

Bonus Objectives Occasionally a random bonus objective will spawn somewhere in the world. You have a limited amount of time to activate the objective. Successfully completing the objective will grant points based on how well you performed.

Control Point
Stand in the control point to gain progress. Reaching 100% progress completes the objective, and awards points based on how much time is left. If the timer reaches 0 the objective is failed. Capture progress is scaled based on how many players are in the game.

Headshots
Secure a set amount of headshot eliminations before the timer reaches 0. Progress is scaled based on how many players are in the game. Points are awarded based on how much time is left upon completion.

Delivery
Deliver 4 objects randomly placed in the world to the objective location. Points are awarded based on how much time is left upon completion.

Defend
Defend the objective position from incoming bots for 2 minutes. Bots reaching the objective location reduces the objective health. If objective health reaches 0, the objective is lost. If the objective is still standing when the timer reaches 0, points are awarded based on how much health is left. Damage to the objective is scaled based on how many players are in the game.

Power In the red room, you can activate the "Power" which enables the shop in the red room. You can find the Shop Key (a turquoise circle) placed randomly on the map to open the shop. The shop stays open for a minute, where you can purchase upgrades to increase your Damage, Healing Output, or Max Health permanently.

Elites As players gain large amounts of stat boosts from the shop, regular enemies become replaced with clearly identifiable elite enemies with more health and strength. Players who find themselves in later stages with a lot of points in Health, Damage, and Healing will be met with a tougher challenge!

Mystery Tank Whenever the power is activated, several upgrades appear across the map. One upgrade is a "Mystery Tank", which appears in Hammond's room. Here you can spend points to gain a tank character and a certain amount of energy based on the current Round number. You can hold reload to swap between your hero and your tank. Killing an enemy as your tank reduces your energy by 1. Upon depleted energy, the tank is lost. Upon dying as your tank, your tank is lost and you get instantly revived.

Nano-Upgrade
Another upgrade you can purchase is "Nano-Upgrade", which provides a hero-specific upgrade until you go down.

Ana (Sleep Dart+) - Sleep dart grants ultimate, knocks down victim, and causes damage over time.
Ashe (Viper+) - Each primary fire hit stuns the victim for 1 second.
Baptiste (Biotic Launcher+) - Each heal with secondary fire grants immortality for 5 seconds.
Bastion (Sentry+) - Each primary fire hit in sentry mode deals knockback to the victim
Brigitte (Repair Pack+) - Healing with repair pack grants armor based on how much health is missing.
Doomfist (Rocket Punch+) - Successfully landing a rocket punch causes the victim to be knocked down for 2 seconds, and decreases Rocket Punch cooldown.
Echo (Focus Beam+) - Damaging enemies with the BIG-BEAM-BIG-DAMAGE-LASER instantly freezes the enemies. Securing an elimination with it resets the cooldown.
Genji (Dragonblade+) - Dragonblade deals 50% of the enemy's health in damage on top of the base damage. 75% Ult Charge is refunded after blade is sheathed.
Hanzo (Stormbow+) - Stormbow damage resets the stormbow ability, and damages all enemies near the victim.
Junkrat (Steel Trap+) - Steel trap stuns enemy for 8 seconds, and resets trap cooldown.
Lucio (Emote+) - Emoting causes bursts of healing for teammates, and damage/knockback for enemies.
McCree (Roll+) - Rolling nearby enemies trips them and knocks them down for 5 seconds, and dealing damage.
Mei (Endothermic Blaster+) - Each hit with Mei's gun instantly freezes the victim for 2 seconds.
Mercy (Resurrect+) - Resurrect is instant, heavily damages nearby enemies, and reduces the cooldown of resurrect.
Moira (Biotic Orb+) - Healing with biotic orb grants phased out for 5 seconds. Damaging with biotic orb puts the victim to sleep for 8 seconds if their health is below 33%.
Pharah (Jump Jet+) - Using Jump Jet grants Pharah shields for a few seconds, refreshes her rocket fuel, and greatly increases projectile speed.
Reaper (Shadowstep+) - Using shadowstep grants phased out for the duration, and stuns nearby enemies for 3 seconds. Also roots nearby enemies for 6 seconds.
Soldier: 76 (Biotic Rifle+) - Primary fire hits to an enemy below 25% health instantly kills them.
Sombra (Stealth+) - Become phased out while invisible, and hack enemies by walking through them.
Symmetra (Photon Barrier+) - Symmetra's primary fire chains to nearby enemies, dealing a fraction of the original damage to each chained enemy. Works through walls.
Torbjorn (Forge Hammer+) - Dealing damage with the forge hammer deals increased damage, stuns the enemy for 1 second, and resets Overload cooldown.
Tracer (Pulse Bomb+) - Tracer's ultimate charge starts at 50%. Pulse bomb damage instakills victims and chains to any enemies within 8 meters of the previous victim.
Widowmaker (Widow's Kiss+) - Any scoped damage brings the enemy down to 1 health if it doesn't kill them, heals Widowmaker for damage dealt, and resets grapple cooldown.
Zenyatta (Harmony Orb+) - Dealing healing with Harmony Orb to an ally with less than 33% health teleports Zenyatta to the ally and automatically activates Transcendence.
D.va (Self Destruct+) - Self destruct nukes all enemies on the map.
Orisa (Fusion Driver+) - Fusion driver roots the target and teleports nearby enemies to the target's position, clumping them together.
Reinhardt (Firestrike+) - Firestrike lights victim on fire, and damages over time.
Roadhog (Whole Hog+) - Ultimate damage briefly stuns enemy, roots them for 30 seconds.
Sigma (Kinetic Grasp+) - Kinetic Grasp pulls enemies within view angle and holds them in front of Sigma for the duration of the ability.
Winston (Primal Rage+) - Using Primal rage terrifies all enemies and causes them to run away from the nearest ulting Winston.
Wrecking Ball (Roll+) - Dealing damage while rolling knocks the victim down for 3 seconds, and deals additional damage after 2 seconds.
Zarya (Particle Barrier+) - Shielding self instantly grants charge, and adds shields to Zarya's health. Shielding ally adds additional shields to ally's health.

Two other upgrades are available as well, "Lucio Headphones" and "Akande Gloves". Each of these have 3 levels you can purchase, which get more expensive and more powerful with each level. Lucio Headphones increase your movement speed, while Akande Gloves increase your quick melee damage.