Pacific Heron
Even in calm seas, Port Trafalgar can be a dangerous place...

So, many of you have seen some of my aesthetic maps. I've decided to deviate from this, and thus I present the 'Pacific Heron', a large scale Invasion map centered around the Armed Merchant Ship (AMS) Pacific Heron, a Cargo Ship named after the real Pacific Heron, a freighter used to transport nuclear materials and one of the few merchant ships legally armed with deck guns and heavy weapons.

Backstory:

On an outer UNSC colony, ruins from a Forerunner outpost were discovered. After imposing a military lock-down, the UNSC began the excavation. Not long afterwards, a Covenant scout ship arrives, only to be met by a large UNSC force. The ship was destroyed, but the UNSC brass was now concerned about the artifacts' safety, and have ordered all finds to be taken off-world.
The Pacific Heron has been commendered by the military and converted from a normal freighter to an impromptu UNSC naval battleship. It has been tasked with moving all the artifacts (the most precious being a navigation core) to Port Trafalgar, which is situated right next to the planet's Spaceport. There the artifacts will be picked up by a UNSC Destroyer and taken to a secure location.
However, not all the Elites on the Scout Ship died, and unknown to the Heron they have covertly taken over Port Trafalgar and are planing a last-ditch ambush.

While it will play normal with Slayer, Infection, and Team Slayer (I'll get to this later), this is a very tactical Invasion game. If your team does not communicate and work together, it's likely you will be devastated.

Note: (This Invasion game was meant for 16 players, and I haven't been able to test it with a party anywhere near this size. This is a version 1, and this is why I've posted it in aesthetics. If someone could test it with a full party and send me a video that I could study, I would really appreciate it.)

Now, onto the map. I'll start with the ship itself and move onto Invasion later.

Here's an overview of the ship. It's armament: 2 Scorpion "Deck Guns", 2 Scorpion "Side Guns", 2 Rocket Hog "Turrets", and 2 Shade turrets. You would think that would be impossible to attack, but all the "turrets" have very limited field of fire, and only when gunners work together can you successfully defend the ship. Also, distant people and fast moving Falcons aren't easy targets. And yes, I've made sure the tanks respawn fine, can't escape, and that players don't get trapped in the boxes. More on the guns later.

Also, all the scenery you see ends up having a purpose at some point in invasion...

Port Trafalgar ahead... but something feels off...

The ships main deck guns. There are a few bunkers on the hill that house heavy weapons for the attackers. There's cover up there, but it is sparse and no attacker's weapon is a one hit kill so pay attention. The attackers who decide to take the bunkers have to cover their falcons as they try to drop troops off on the ship, otherwise they won't get through.
The top deck gun can hit all three bunkers, the lower can only hit 2 because I limited its field of view. These guns have a good field of view but cannot hit anything forward of the ship or down low.

Mid deck guns. They can't hit the bunkers, but can fire at Falcons trying to come in fast and low at the sides. (Note: all Scorpions have a weak spot, their backs where you 'board' them are perfectly exposed... 1 grenade aught to do it.)

Here you can see the central ramp down, and more cargo crates...

A view of the lower cargo hold.

More pics:
Bungie.net : Halo Reach : Recent Screenshots

Invasion:
Here is a quick overview of Invasion on this map.

The whole view of the map, with the attackers base. This view is the attacker's start up cam.

Focus on the Blue (Elite/Attackers) base. Some simple aesthetic detail here.

Right by the initial spawn are 2 mongooses (or mongi?) These give attackers quick access to the bunkers and weapons inside of them. I had to put that catch there, every time I drove off.
It's important that some of the attackers go to these bases, otherwise it could be a turkey shoot for your Falcons. Tactics, people!

The bunkers themselves. From left to right, 1 rocket launcher, 1 spartan laser, and 1 sniper rifle, all with a fair share of ammo. Also, behind one of those rocks and leaning on the tree are a RL and a sniper.

If you've snuck around back, there's a fairly open landing pad for you, but it forces you through some tight-quarter rooms where defenders may be lurking... also, there's a hole on the top of the bridge for quick access.
Note to shade gunners: your plasma cannot reach the bunkers on the hill, so unless there are some Falcons to shoot at you might want to lay low, as you're susceptible to sniper fire. However, you have a good view of the lower access ramps and deck where sneaky pilots might try and drop off troops. Also, by the last phase, your role has increased greatly: the core carrier has to pass both shade gunners to reach the objective, and you can create quite an obstacle. However, you'll still be a sniper magnet.

Elite's Objective 1: Bomb the ships engines, so it can't escape. There's a waypoint for you, but if you're curious the engines are located past the med bay, and before the galley. Also, as a side note, the bomb has a fairly fast reset. This is because it does not automatically reset if it falls into the ocean. Don't put it down for kicks.

The Forerunner artifact is inside the locked crate. By taking down the power and security mainframe, you can open the crate and make off with the core.

Bombed the engines? RTB and grab your hacking kit. Your prize is the forerunner navigation core, and the Pacific Heron's back up generator/computer core has it locked down tight (This mainframe is attached to the central ramp). The area you have to stand in is small to simulate you hacking it. This means bring a buddy to cover you.

And now the Forerunner core is exposed. Take it, and victory is yours! By this point, the defenders claim on the ship's deck is probably slipping, but with the classes at your disposal you'll be prepared to fight on-board.

The core's final destination is a small research station off the coast. By taking the core, the building's garage opens up and a man-cannon appears on the roof of the ship's bridge. Fight your way through the ship and to the bridge to reach the cannon.
This pic is on the bridge. The ramp to the roof is on the other side of the room. Note the sniper rifle in this room. It only has one clip, but the idea is strategy. Someone can stay in the protected bridge and scope in on targets, and tell their gunners where to shoot. It can be hard to see that far away with the scorpion, but with some teamwork they can become deadly accurate.

The research station, garage open. I tried a variety of methods to save you after the massive leap from the 'Pacific Heron', but this 5x5 block proved the most effective, as well as cheap. It's taken my shields down a tiny bit but never killed me no matter how you enter it.

And that's it for Invasion! After their victory, the elites utilize stolen transport at the Port to make off with the stolen artifact. (I had such a hard time not calling this game Somali Pirates.)

Also supports Slayer, Team Slayer, and Infection. All these game types solely take place on the ship. If you are to play any of these, I would suggest customizing your game type to take weapons off the map and have loadouts, because I did not have budget to spare to place weapons for anything but invasion. I may make a version of this map that is only the ship, and has balanced weapons on it (If I delete all the stuff off the map for invasion I should have the budget). You do not need to worry about the vehicles in these gametypes, as the shade turrets go away and the rest cannot be used on the deck (you usually end up killing yourself).

TLDR: I suggest SWAT, but with vehicles on map.

Remember to comment and if you can test this with a big party make a video and send it to me. I plan on making several improved versions of this map. Grand, super-team oriented battles are what I've always wanted from Halo, so I hope this is a realization of that.

-Lazer X7