Coagulation was one of the larger style maps in Halo 2. It was a remake of the map from Halo 1, Blood Gulch. The map is a symmetrical field, with a base at either end. Other than that, the map is fairly open. There is a ledge walk way leading to a cave outside the Red Base, and a ledge walkway leading to a cliff that can see the entire map at the Blue Base. The map, back during Halo 2's prime, was loved by pretty much everyone.
 Preferable Game Types
Coagulation was another map that took to any game type well. Slayer variants all worked well because the map was not completely flat. If you thought it was going to be easy to see where your enemy was just because the map was a big field, you were going to die. Balanced weapon spawns and smaller team games made for sometimes tense and down to the wire games on Coag.
In truth, though, Objective games are where Coag really shines. The map is so large and perfectly balanced that any game of Assault of CTF turned into an epic firefight multiple times during the game, for the simple reason that the map was so often. Unless you managed to nab a flag and get a perfect run right back to your base, no interruptions, you would be in for a rough time attacking for your flag again if you dropped it in the middle of the field. This lead to incredibly fun gameplay though, because having a huge gunfight in a big team battle in the middle of the Coagulation gulch was probably one of the most memorable things you could ever do in Halo 2.
Assault was much the same story. The element of surprise was your best friend on Coagulation. There was always the "It's too quiet" factor while you're on defense, and you never knew which way the attack was going to come from.
Vehicle spawns on Coagulation are variant specific. On a regular 4v4 slayer, you can expect to see only a Warthog or Ghost. Up the ante to a Big Team Battle though, and you'll find Banshees, Scorpions and Wraiths spawning at each base too. With more players comes more mayhem.
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