Note: There was a huge decrease in XP gain from Invasion bosses so while it is still one of the faster ways, it is no longer as quick as before (RIP to all the XP data I was collecting). Invasions like at Navarra are now more commonly used to farm gold and cores due to the high density of mobs, and bosses are now largely ignored.
Invasions have easily been the best method for XP as well as giving abundant gold and gear for cores; hence the sudden surge in max levels when invasions were changed to reset every 8 hours. However, not everyone is clear on what invasions are or how to make the most of them so I've made this 'little' guide to help you all. Huge shoutout to Bai on making the first proper explanation on invasions and how to trigger them (can be read here).
In this guide I will try to explain what invasions are, where to find them, how to trigger each one, and how to get the most XP with videos of ideal routes and pictures of boss spawn locations.
Who needs invasions?
Invasions are important to everyone: it is the best place for XP, making it good for all levels; it can make you easy Star Seeds as there is constant demand for the rewarding essence; it gets you a lot of gear, making it useful for cores; and you can drop a lot of potions and other random rewards.
Your level and gear score is largely irrelevant, as even a level 1 with just a weapon can get one hit on a boss and reap the rewards while everyone else kills it. However, it is recommended for those of a gear score above 840 as you will otherwise deal negligible damage and may die very frequently as the bosses are high level and hit hard.
What are invasions and what's their point?
Invasions are triggered events where lesser Chaos Gods try to invade Lumios by sending in their armies at specific locations (so much for Physera "guarding" the Chaos realm to prevent this). Your job is to repel their armies by completing certain objectives - the more you help in an invasion, the higher your contribution. Gameplay wise this involves the below steps:
First, you need to trigger the invasion. For most invasions that means simply killing a lot of mobs within the area (the specific triggers are further in the guide).
After the invasion has been triggered, the atmosphere will change and Lumios will be invaded. You will receive objectives where your quests are usually listed (if this is not visible, cancel tracking one of your side quests - usually Union quests). These objectives will typically be "kill x amount of enemies", "kill up to 6 bosses", and sometimes an objective that requires interaction like "light 20 braziers" or "free 40 captives".
Below your objectives will be your Contribution bar and grade. This starts at Grade 3 and goes up to Grade 1, giving you better rewards at higher grades.
Unfortunately grade 1 is impossible unless you have an invasion to yourself as you need to contribute to over 80% of the tasks. Grade 2 is possible in only a few invasions and not really worth the effort as you sacrifice millions of XP for everyone. Moreover, completing all interaction objectives does not guarantee Grade 2.
The invasion lasts 40 minutes and your theoretical task is to complete all these objectives within that time. After completion a giant chest will spawn with your rewards - if you do not collect it then it will be mailed to you. If you fail an invasion you will not receive a chest, unlike some Crusades.
The point of invasions from the game's perspective is the reward - essence - which is required to unlock the Storm Chaser blessing. Once you collect a specific amount of a set essence, you can take it to a Reputation Merchant with whom you have Revered reputation to exchange for a Memory Fragment: Storm Chaser I - V. The below table from Bai's Reddit post shows how much you need and from which region's faction:
Each invasion has a specific essence that it provides. At Contribution 3 you receive 20 Essence, 50 at Grade 2, and 100 at Grade 1. However you can also get essence from the mobs and bosses, so the longer an invasion goes on and the more bosses you kill, the more essence you can get. Below is a map of where each invasion is located as well as what essence it drops and how much of it you need in total.
How to trigger an invasion
At each invasion there will be an altar in the area and provided you have gone far enough in the story line you should be able to see it. Over the invasion icon on your map there will be a timer, like in the picture to the right (or above on mobile), and when that timer reaches 00:00 you can touch the altar to begin triggering the invasion.
Each of the invasions has its own trigger. Bai was the first one to share these triggers before the game even showed us timers, so huge respect to him and his team for getting this info and for letting me share it here as well. Working from the top down from the invasion map, the triggers are as follows:
Creatures of Chaos (Kannus Mountains):
The Cursed Mountain crusade (north-east of the invasion, above the Two-headed Wyvern) needs to be completed 3 times after the invasion is available. Simply touch the invasion altar at Rutus Road before starting the crusade.
A Frozen Fate (North Sperios):
Kill Footpads after touching the altar.
Seed of Destruction (Padana):
Kill Nightrunners after touching the altar.
A Searing Assault (South Sperios):
Kill Footpads after touching the altar.
The Cult of the Purifiers (Navarra):
Touch the altar and slaughter Wild Horn Buffalo.
A Spreading Blight (Carzacor):
A level 28 treant entitled "Messenger of Destruction" will spawn after touching the altar. Kill it to begin the invasion.
Warriors of the Jungle (Gnoll Wastes):
Touch the altar and kill 100 Drysand Choppers (not pumas!), as confirmed by GMKanz.
A Spreading Darkness (Tristezza):
Touch the altar and kill 6 cyclops. The respawn timer for cyclops is 28 minutes so after the first and/or second waves, if another invasion is available most people will rightly go for that one instead and come back afterwards.
Subterranean Invader (Zenkala):
Touch the altar and kill 3 Volcanic Wyverns.
Discord and Disease (Timeless Jungle):
Touch the altar and butcher the local wildlife.
The total amount of kills does not change according to whether you kill all mobs on one channel or across them both, however they will often need to be done between multiple channels to utilise their individual spawn rates. As such, you should remember to switch back to channel 1 after the invasion starts as this will have the majority of the players, which is helpful as it hastens the boss kills.
Important comments on the altars:
Once touched, the altars have a 10 minute cooldown before they can be groped again, however this does not reset progress on triggering the invasion so feel free to touch it as often as you please.
This likewise means there is no specific timing as to when to touch it - so don't think that someone touching it will be of any detriment to triggering the invasion.
Touching an altar on one channel activates the 'trigger phase' across all channels, so if you activate it on channel 1 but kill a cyclops on channel 2, it will still count towards activating the rift invasion.
Each channel has its own altar with an independent cooldown. This means that even if someone touches it on channel 1, someone else can touch it again on channel 2 without waiting for channel 1's cooldown.
When an altar is activated or within its cooldown while you are outside its render distance, it can sometimes become invisible when you arrive at its location. So if you turn up to the altar and it is not there, that means it has already been activated before you arrived. Similarly, if you activate the altar and then move a certain distance away, it will not be there upon your return until the cooldown is over.
While there has been no observable time limit between when you touch an altar and when you complete the requirement, it is generally good practice to touch the altar at Rutus Road before starting the Cursed Mountain crusade. Don't assume the crusade before you was done correctly.
Below are some pictures of the altars so you can find them and trigger the invasions.
How to get millions of XP
Firstly, note that the XP gained scales with your level and per boss you get roughly what you would from a field boss regional. It is vital that you do invasions solo! Being in a party reduces your XP by 50%. Use PvE Combat XP boosters whenever possible.
Earlier I referred to your "theoretical" task as being to complete the objectives. That's because in reality, none of those objectives matter. You go to an invasion to kill the bosses, netting you all the goodies I mentioned before plus the fastest level gains you can possibly achieve. You do not go to an invasion to get Grade 2 contribution - the only way to do so would be to get a hit on as many mobs as possible and doing the interaction objectives, however by doing these you end the invasion prematurely for an extra 10-30 essence. There are better ways to get essence without being selfish - further below I'll explain how best to get essence.
Every invasion has predetermined boss spawns - go to a spawn, kill the boss, go to the next spawn, kill the boss, and so on. That's it. Simple, but repetitive.
Invasion bosses take 2 minutes to respawn in all regions. This has been reduced from the previous 1 minute timer, so you have plenty of time to kill three bosses in invasions that have them. Moreover, you will notice that bosses may not always render in for you before they die; this is why a lot of people start attacking with AOE (Area Of Effect) moves around the spawn as these will hit even invisible mobs. When bosses die in under 5 seconds this is crucial or else you may miss the XP.
Here are the main mechanics and 'tactics' per invasion (to save space in this long guide, images and videos are linked - just click the underlined text to see more):
Creatures of Chaos (Kannus Mountains):
There is only 1 boss spawn here and it's a variant of the Two-headed Wyvern. This coupled with the long invasion trigger makes it bad for XP and is best for its essence - so feel free to tag the other mobs to try get Grade 2 contribution. The spawn is marked here.
A Frozen Fate (North Sperios):
This invasion is quick to start, has 3 Ice Giants in one rotation, and a longer interaction objective making it the best for XP farming. This picture has their spawn locations alongside the number which represents the order in which the rotation goes. The ideal route is shown in this video. This can easily last the full 40 minutes of the invasion, so try not to break the ice.
Seed of Destruction (Padana):
Easy to start but chaotic and quick to finish. The space in which the mobs and bosses appear is very close quarters (boss spawns here), making this a chaotic invasion but easy as the players are also densely packed. Unfortunately the side objective is easily completed as the field is abundant with interaction items. Here's some gameplay for reference.
A Searing Assault (South Sperios):
This is easy to start, however as there are no interaction objectives with which to delay its completion, this invasion ends pretty quickly. That being said, this invasion has three boss spawns (see map here) and the route is straightforward (view gameplay). The boss' fire DoT (Damage over Time) can be quite brutal so watch out. Also item beacons are not visible here properly so make sure to actively loot your kills.
The Cult of the Purifiers (Navarra):
This tends to be the most difficult invasion and also one of the most rewarding. The boss can inflict long stuns and bleed plus there are endless little mobs which can kill you while you're stunned. On the other hand, they provide a lot of additional drops and can be hit with AoE moves while focusing the boss. The boss spawns in order are here and the gameplay can be viewed here.
A Spreading Blight (Carzacor):
This invasion offers growth and, like the fire invasions, ends quickly purely due to the demand for its essence. Players try to get grade 2 contribution by chopping down trees (doesn't work unless they tap a lot of kills too) so there's little time for the bosses. These bosses are a pain as they are the fastest mobs, can go underground (tip: mark them in inspection mode and you'll see where they come up from the ground) stack bleed and can stun. A picture of their spawns is here and gameplay can be viewed here. There are 3 spawns however the gameplay shows only the bottom two as the top is rarely used since these take more time to kill with all their time underground.
Warriors of the Jungle (Gnoll Wastes):
One of the longest invasions to trigger. So many pumas have been butchered mercilessly it's a surprise PETA hasn't got involved. A picture of the boss spawns can be found here and gameplay of the full route (all three bosses) is shown in this video.
A Spreading Darkness (Tristezza):
The most simple invasion. There are only two bosses in a straight line from each other and provided people don't light the braziers it can last the full 40 minutes. A picture of the spawns is shown here.
Subterranean Invader (Zenkala):
The trigger is one of the easiest but the reward is awful. Ice essence is overabundant from the North Sperios invasion and has little value. The invasion itself is split into two parts - the first part includes 1 boss and some mobs, which can be powered through (blue icon on the map is its spawn). The second part has two easy bosses - these can be grinded as it's still better than doing nothing in terms of XP, but it'll be slower than other invasions (red icons for their spawns). This might be the easiest invasion in which to get Grade 1 as not many people come to help.
Discord and Disease (Timeless Jungle):
This one is unique in that it has 9 mini-boss spawns. These mini-bosses provide around a quarter of the XP a normal boss would in an invasion, however there are many more spawns beside each other (see here). Unfortunately these also have 2 minute spawn times. Nonetheless with a good team this can be a good XP farm as there are rarely any other players involved. Plus it gives you Chaos essence.
Getting the most essence
For those that don't care for XP and just want to get Storm Chaser (without buying them off the market), the most effective way to do so would be to use 'alts' (alternative accounts). Alts are very useful in general as you can get multiple Star Seed exchanges, multiple estates, and multiple invasion rewards. Using alts is preferable to getting Grade 2 on your main as you only get 30 more essence, which is even more negligible if you would have focused on the bosses and gathered the essence they drop.
To use your alts at invasions, simply take your other accounts to the invasion before it starts and then complete one part of the side objectives with each one. The easiest way is to just get a hit on one of the mobs and after it dies (provided the objective isn't fully maxed already) you can switch accounts and do the same. After the invasion is complete you have 5 minutes to claim the chest at the end - try to claim this chest with each character as it may not be mailed to you.
Generally you will be playing the game for a while (hopefully) so you'll be doing plenty of invasions - there's no rush for Storm Chaser unless you're a priest. For some advice, Chaos essence sells for more than Fire/Growth at times, and you can get a lot by being the one that completes Discord and Disease. Then just sell Chaos and buy Fire/Growth.
Going to an invasion doesn't have any requirements so feel free to just go there and test it out. Fire and Growth essence are the most needed given their over reliance from the Reputation Merchants, so trying to get higher grades or using alts is best saved for those invasions. Another quick point; collecting the chest at the end has a risk in Disputed Zones as some people like to get mass PK's on the chest so you're better off collecting the reward from your mail. That being said, collecting the chest gives you a 50% Attack Power buff for 20 minutes - this buff is only present in the Open World.
Anyway I hope this guide has helped and if there's anything you still want more info on, or spot something that is incorrect, please leave a comment letting me know.
Please update to include ivory dunes. Otherwise, this has been very helpful!
Thank you for the guide! I knew a thing or two beforehand, but having it explained to me was helpful. I like the map. It helps out a lot. I wish I had it when I was getting SC. Now, I can help others or get it on my alt ez.
This guide was extremely helpful! It would be nice to know how many creatures needed to be killed to begin some of the invasions though. For instance, Discord & Disease or any of the others that require kills to trigger the event after activating the alters.