There are seven different colors of ISO-8 in the Facebook game Marvel: Avengers Alliance. Each different color of ISO-8 comes in multiple specific types. Each type grants a hero a bonus to a specific set of stats. Orange ISOs, appropriately enough, offer the combined benefits of red and yellow ISOs. They can increase any stat except for stamina or health and always increase two or three stats. Generally you want to use these on heroes that already have good stamina and health. The following guide to orange ISO-8 in Marvel: Avengers Alliance will give you all the information you need to properly equip your heroes with these ISOs.
Reactive Dexterous ISO-8 (Evasion, Accuracy / 17,500 Silver, 4 SP) – Dexterous is one of the better combinations for general PvE. Avoiding attacks is one of the best ways to maximize your score and hitting is more important than damage, in general, in quickly ending fights in PvE. The Mercurial ISO-8 is better, in general, but this isn’t a bad option if you need to conserve silver or Shield Points.
Reactive Exact ISO-8 (Defense, Accuracy / 18,900 Silver, 4 SP) – Exact is an ISO that you rarely need. Defense isn’t particularly critical and when you do need it, you almost always want to increase health at the same time. Exact is something you should never pay for, but if you do find some, they are better than Precise for increase accuracy, because accuracy alone is essentially always a poor choice.
Reactive Proficient ISO-8 (Attack, Evasion / 18,900 Silver, 4 SP) – If it has no other use, Proficient is easily the best ISO in the game for the Hawkeye heroic battle. He needs to avoid hits desperately and equally needs to defeat enemies in as few attacks as possible. Most heroes prefer Mercurial, but Hawkeye doesn’t need an accuracy boost. Besides this use, attack and evasion are easily the best two stats in the game to increase, so this is a good ISO in general and, since it is relatively cheap in terms of Shield Points, worth buying when you need a quick stat boost for a hero that you aren’t entirely sure how you intend to improve permanently.
Reactive Bulky ISO-8 (Attack, Defense / 20,300 Silver, 4 SP) – There is no good reason that Bulky costs more than Proficient. It is mildly better than Exact, but only by the smallest margin. You should never buy this and only use it when you don’t feel like spending money and don’t have any better ISO for improving attack.
Reactive Mercurial ISO-8 (Attack, Accuracy, Evasion / 24,000 Silver, 5 SP) – Mercurial is surprisingly the second cheapest of the orange ISO-8 that improve three stats, despite easily being the best of the four. For just about any hero that already has good stamina and health, or has a good health and a built in means to recover stamina, like Sabretooth, this is the primary ISO-8 you should slot on that hero. Only two other ISO are conditionally better, Chaotic and Skillful. The conditions that make Mercurial the best of the three are the least common, but still common enough that you will use this often.
Reactive Adroit ISO-8 (Defense, Accuracy, Evasion / 23,400 Silver, 5 SP) – Adroit has the same flaw as Guardian. When evasion works, defense is useless. If you are going to add both of those stats to a hero, Expert is your better choice in almost all situations.
Reactive Expert ISO-8 (Defense, Attack, Evasion / 24,600 Silver, 5 SP) – Expert is a common choice for many infiltrators. You want infiltrators to be attacked, because that is how you take advantage of combat reflexes. Preferably your hero will evade the attack, but when that fails, defense is a good backup. Finally, by increasing attack, you increase the damage your hero deals in retaliation. It isn’t perfect for every infiltrator, but it should be one of your go-to ISO for any hero that counterattacks regularly.
Reactive Forceful ISO-8 (Attack, Defense, Accuracy / 25,200 Silver, 5 SP) – Forceful is essentially the less useful version of Mercurial. Instead of increasing your hero’s chance to outright avoid an attack, it simply decreases the damage the hero receives when hit. Skillful is basically purely optimal and you should only use Forceful when you have some in inventory and simply can’t afford to spend either silver or Shield Points.