If you are wondering what is Meta-Game, this Halo 3 Guide will provide you the answer.

Halo 3 Meta-Game adds another dimension to the Halo 3 gaming experience. When Campaign Meta-Game is turned on, you will earn points for every enemy that you kill. Of the 49 Achievements, there are 9 Achievements which require you to score over 15,000 meta-game points for each of the missions.

To turn on Campaign Scoring, press X at the Campaign Lobby screen. Next, push the Left Thumb-stick to the left or right to select the Off (Default), Free For All or Team setting and then press A. If you are playing Solo, either the Free For All or Team setting will do. For Co-Op, the Team setting will display only one total score, whereas the Free for All setting will maintain individual scores for each of the players.

The points earned will be displayed on the bottom right section of the screen. There is a base value for each enemies. A Grunt kill is worth 5 points while a Chieftain and hunter is worth 150 points each. However, the points can be increased by multipliers, which depends on the difficulty level, killing style and skull multipliers. Howeve, if you are killed  25 base points x multiplier factor, will be deducted immediately.

The higher the difficulty level, the more points you will earn with each kill. The difficulty multiplier is as follows: Easy (0.25x), Normal (1x), Heroic (2x) and Legendary (4x). The style multiplier is 1.25, when you kill the enemies with Grenade Sticks, Headshot kills, Stealth (cloaking) kills, road kills, Multi-kills and Needler kills.

When you activate the Skulls, the Skull Multiplier will be as follows:

3x for the Iron Skull,

2x for the Famine, Tilt and Mythic Skulls

1.5x for the rest of the gold skulls

For example, if you are on Legendary Difficulty (4x) with Iron Skull (3x) and Famine Skull (2x) activated, and you kills a Brute (20 points) with a head-shot (1.25x), you will earn 20 x 1.25 x ( 4 + 3 + 2) = 225 points.

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