Some parts of the AI are not unit specific, but apply to all of them. By editing these parts, the Better AI can improve the general behavior of enemies on the field.
Increased cover weights
When deciding on how valuable tiles are, cover applies a bonus to this value. These bonuses have all been increased considerably. The old bonuses were +0% for mid cover (yes, really) and +10% for full cover. Leaders had a special treatment that made them value full cover at +150%. Or in other words, other than pod leaders, enemies basically do not care much about cover in vanilla XCOM. Once you realize that there’s also the Lingering penalty of -25%, it doesn’t surprise much that vanilla AI has no cover discipline at all. They do get some additional cover preference out of the type of movement they want to do (flanking, retreating, advancing, etc…), but the lack of a solid cover weight baseline made enemies not aware enough of how important cover is to their survival. A Better ADVENT changes these values to +50% for mid cover, +150% for high cover and +200% for pod leaders and high cover. This leads to a much better scaling cover weight. Once the additional weights from the movement profiles are also considered and with the lingering penalty reduced significantly, enemies will pretty much stick to the same “low cover is no cover” mantra that players have been using for years.
Priority Shots
With ABA, enemies will now jump at the chance to cause some impactful damage to XCOM. When deciding on which shots to take (if any), several types of priority shots are considered first, overriding vanilla targeting. Only shots with a chance to hit of at least 40% are considered for priority treatment.
- Flanked Shots. If a unit has a target flanked, he should take that shot. No considering about other targets, no raising of Zombies, just pop that guy that’s standing in the open. This shot usually has the highest priority of all.
- Kill Shots. If a unit could potentially kill someone, that’s worth trying. Making XCOM lose a soldier is worth more than wounding 5 of them.
- Sure Shots. Many aliens have a fairly lousy chance to hit, so whenever they get a clean shot, they better take it. Everything with a hitchance > 80% is considered a “Sure Shot” in this context and gets priority over regular shots.
- Shots on Suppressors: If XCOM has any soldiers applying suppression fire on an alien, other aliens will try to break the supression by wounding the soldier.
- Shots on Overwatchers: Just like with Suppression, trying to cancel Overwatches to deny XCOM cheap shots is worth an extra consideration.
Improved reactions to being flanked
The vanilla AI is very predictable in that they will always move if they are being flanked. This can be abused in a number of ways to herd aliens around and into overwatches. The Better AI introduces some sanity checks for the enemy’s behavior, allowing them to react according to the current situation. If Overwatchers or Suppressors are around, the alien will likely take a shot or use an ability instead of triggering all those reaction shots. This is especially true if it is in a two-way flank with the XCOM soldier. If it decides that moving is safe enough, it will also try to counterflank the enemy.
Improved reactions to being suppressed
Suppression is ignored by the unmodded AI, which is why in vanilla XCOM, a suppressed unit will usually move with its first action, thus triggering the reaction fire. With A Better ADVENT, the enemies weigh their options more carefully. These options are using skills, running the suppression, hunkering down or just taking the penalized shot. High dodge values and/or high remaining hit points make running the suppression more likely, so does the potential for a flanking movement. There is a large number of skills that are considered for use while being suppressed, mostly those that don’t need to pass a hit roll. Psi powers, Mark Target and grenades would be examples. So is counter suppression, of course.
Increased range and chance for fleeing
When a unit is alone in his pod, it will search within a certain range for another pod to flee to. The decision to stay or flee is left to a random roll against a percentage. The range in which a unit looks for a potential new pod has been increased from 5 to 8, the chance to flee from 50% to 70%. This makes it much more likely that an outgunned unit tries to save itself by reinforcing another nearby pod of enemies.
Better movement profiles
There are several profiles that set up how an alien decides how valuable tiles are for movement. Factors are things like cover, distance to enemies, flanking shots possible, allies in line of sight and a couple others. These have been tweaked, again mostly with regards to cover, but also in a few other areas where the value looked a bit off. New movement profiles were also created.
More realistic Mimic Beacon behavior
One of those movement profiles takes over whenever there’s a Mimic Beacon in sight. In vanilla XCOM, this profile takes no regard at all for the aliens safety, which is just unrealistic. It has been changed so that aliens still go for the Mimic Beacon with their actions, but keep on using cover, staying apart from each other and don’t run into flanks. Basically, they treat the Mimic Beacon as any other enemy, but give him high target priority.
Panicked soldiers are no longer safe
Enemies in vanilla XCOM don’t target panicked units unless there’s nothing else to shoot – even when that target is being flanked. Basically, getting panic on your soldier would make him invulnerable for a turn or two. This behavior has been removed completely, shooting at panicked units is absolutely something that enemies should do.