The Retribution
Created by The Abhorrent

Map Description
My first attempt at an Invasion themed map, along with one which changes rather dramatically as the match goes on. The premise is for the Spartans to board the Convenant vessel, The Retribution, and take it down from within. I used a couple of SFX orbs to give it a nighttime look. This map effectively requires the custom gametype, though theoretically it is possible to use the basic Invasion gametype as well.

EDIT: Added a version of the map without SFX orbs to FileShare.

EDIT: Added another version, more of a corrected version of the original. Didn't know you could choose the respawn zones when I first made this map, and it's been corrected in the Mk. II version (added a some more choices for Phase III too); barricade is also been fixed. No SFX-less version of the Mk.II, File Share is a little "full" right now.

Phases

Note: All phases last five minutes, and the game lasts for two rounds.

Phase I - Boarding the Ship and Disabling the Turrets
Spartans start a fair distance away from the ship, on the clifftop on the far end of the map; Elites are restricted to the lowest levels of the ship for the first phase. Spartans begin with four Falcons (but how many players per Falcon? that's up to the team to decide), giving the needed transport to the vessel. Elites have four Shade Turrets to fight them off, and two detachable Plasma Turrets within the interior of the "hangar" where Falcons may fly in. The are two possible territories to capture (taking 15 seconds to do so), one placed directly behind the lower pair of the Shades and the other between the Plasma Turrets. Teleporters allow players to move between the two levels where the Shades are found. There are four access routes for the Spartans: the lower hangar (go below the Shades and into the large opening at the front, only place the Falcons can fly into the ship during Phase 1), the platform between the lower Shades, anywhere you can find near the upper Shades, and the rear landing pad of the hangar.

Phase II - Special Delivery: One Military-Grade Can-Opener
The second phase is a guantlet event for the Spartans, they need to get the bomb from their new spawn location to the reactor at the far end of the ship. Elites have the supposedly simple task of stopping them. There are multiple paths for the Spartans to take, two levels along the central path (both lined with ample barricades for cover), both of which are divided by a wall. The two rooms just to the side of the Spartans respawn location contain teleporters which send the player a good distance up the guantlet on the same side. The bomb has a very short arming timer and fuse, meaning it's not possible to disarm.... or escape the explosion if you were the carrier.

Phase III - Abandon Ship!... and don't forget the core!
Completing Phase II has the expected result of detonating a bomb near a ships reactor-core: it starts to blow up! The reactor and many of the surrounding walls are removed during this phase. Plasma-leaks (aka: man-cannons and gravity lifts) allow the player to move around the ship. The uppermost levels of the ship are unlocked during this phase, and the core to be captured is located at what could be called the "Command Deck" of the ship. Anyone who didn't get killed by the bomb at the end of phase 2 but is still nearby may take a ride on a plasma-leak up to it. Getting the core out is a long haul, as the carrier must bring it back to the rear hangar and jump into the spaceship which spawned beneath The Retribution. Take any route you please, even hopping down the platforms if you must. The bottom of the hangar is no longer there (also taken out by the explosion), so you have to find the way across.

Loadouts

Notes:

There are no weapons or armor abilities on the map, everything is provided by loadouts or is scavenged off the fallen.
All players have infinite ammo.
Grenades are staged. Spartans have none in Phase I and two frags in Phase II; Elites have two plasmas for the Phases I & II. Both sides get two of each for Phase III.
Loadouts are staged. Phase I only allows access to #1 and #2. Phase II unlocks #3. Phase III unlocks #4 and #5.

Spartans
#1 - Spec Ops: DMR, Assault Rifle, Hologram
#2 - Grenadier: Grenade Launcher, Magnum, Armor Lock
#3 - Maverick: Shotgun, Magnum, Drop Shield
#4 - Air Assault: DMR, Spartan Laser, Jet Pack
#5 - Berserker: Golf Club, Rocket Launcher, Sprint (Where's that gopher?)

Elites
#1 - Warrior: Needle Rifle, Plasma Rifle, Drop Shield
#2 - Specter: Plasma Repeater, Needler, Active Camo
#3 - Warden: Concussion Rifle, Spiker, Armor Lock
#4 - Ranger: Focus Rifle, Plasma Repeater, Jet Pack
#5 - Zealot: Energy Sword, Fuel Rod Gun, Evade

Core/Bomb Carrier Special Traits:

150% Damage Resistance
200% Health & Shields Recharge Rate
200% Melee Damage
150% Gravity (the damn things are heavy!)

Images

Profile of the ship before during Phase I.

View of hangar, looking backwards

View of gauntlet from Spartan side

The bomb taking out the back of the ship

View of top deck

Time to get out of here!

Regarding Special FX Orbs, ~~feel free to remove them if you don't like the night-time motif. They can be found in the under-carriage of the ship, towards the back end.~~ Or you may download the bright version instead. It's the same map, just a lot brighter (and fixed a minor despawning error).

Otherwise, enjoy trying to (stop other people form) blow(ing) this thing up!