Developed at Kane's behest before the Third Tiberium War, the catalyst missile was created as a counter against the Scrin. The warheads cause Tiberium to chain react when detonated, which suggests it may be liquid Tiberium-based.
The majority of Catalyst missiles are equipped with fairly low-yield warheads that nevertheless can prove very destructive when Tiberium is present. Tiberium refineries stocked with Tiberium were particularly vulnerable targets, as were, as Kane rightly predicted, the Tiberium-based Scrin.
|“|| I knew there was a chance the visitors may not be entirely... cooperative. And that's why I developed a weapon to target their weakness. This will allow you to claim one of their towers, but you must act fast. The visitors begin attacking the facility as we speak: secure the facility, and feel free to test out this new... addition to your arsenal...|
You secured the base but the aliens have already reinforcements to the north. Let's show them your newest toy.
At least one missile equipped with a more damaging warhead, capable of destruction over a larger area, is known to have been produced during the Third Tiberium War and deployed against the Scrin in northern Italy. Despite acknowledging the Scrin as "visitors" Kane was aware that they might not be cooperative. The altered catalyst missile was developed at facility in Northern Italy, however, the Scrin attacked and damaged the facility. A Nod commander managed to retake the base and used either the missile or conventional forces to obliterate the Scrin in the surrounding area. This allowed the Brotherhood to maneuver more troops into place in order to take over a Relay Node, and ultimately, a Threshold tower.
The Catalyst Missile was almost next to useless against most vehicles and infantry (only units enhanced with tiberium were in danger) however, any unit caught in a tiberium field struck by a catalyst missle were prone to take heavy damage. The missile system gains a new level of power when used against Tiberium Refineries, Tiberium Spikes, Tiberium Harvesters, or anything that contains Tiberium which would be destroyed in one hit. This made it easy for Nod to cripple an opponent's economy if they only have few Refineries and Harvesters.
The most practical and frequent use of Catalyst Missiles in-game are for targeting the refineries of any faction; any refinery within the area of effect will be instantly destroyed. The best time to use this weapon is to time it with the docking of a Tiberium Harvester, that way the harvester is destroyed as well. Anything within or near a Tiberium field also will take some damage, although it is often not enough to justify the 2000 credit cost of deploying the missile (as of newer patches - original cost was 1500). Destroying a 3000 (or 2000, in the vanilla game) credit refinery and harvester with the 2000 credit warhead is a great way of disrupting your opponent's economy to throw them off balance, as well as a logically cost efficient attack, especially if the harvester is blown up while its full of tiberium.
The Scrin are especially vulnerable to it as their life and technology is tiberium-based, as a result, any type of Scrin unit or building will suffer fairly significant damage from being hit by a Catalyst Missile. Against the Scrin it is effective for general fire support when necessary, and also for damaging any power plants that might be close to each other; destroying a couple of Scrin plants may be what is needed to knock their defenses offline or create enough chaos due to power shortage to turn the tide in a battle.
It should be noted that the missile always does some damage to infantry that are directly around the impact area, even if there are no tiberium or Scrin units to 'catalyze' the explosion. The damage is incredibly low in these circumstances, but occasionally it can be enough to make a difference in a desperate situation.
In Kane's Wrath, once a Nod commander has a Tiberium Chemical Plant available, it might be a good idea for other commanders/foremen to pay heed; if the commander in question has saved up a stockpile of credits the next thing they may do is immediately launch a Catalyst Missile and use the Tiberium Vein Detonation power in conjunction to wreck the economies of their competitors by destroying harvesters and refineries in large numbers.