Every 35 minutes, a swarm has 75% chance of appearing in a random unlocked area. The timer supposedly starts when the game is loaded.
Once it appears, the swarm stays for 30 minutes, until the game is closed or until cleared, whichever comes first.
Swarms come in 3 variants: regular, large and epic.
Each swarms multiplies monster count and has a minimum monster count on top of that. A wave with insufficient monster count will get additional “normal” type monsters to meet the minimum (even in areas that don’t normally spawn “normal” monsters).
A swarm is cleared when you get at least as many clears in its area as it takes to clear it.
The difference is in monster count, clears needed and common talisman reward.
- * Regular swarm requires 50 clears, has x3 monster count (min 10), rewards 1 talisman* Large swarm requires 150 clears, has x4 monster count (min 15), rewards 2 talismans* Epic swarm requires 300 clears, has x5 monster count (min 20), rewards 3 talismans
The base spawn chances are 85% for regular, 13% for large and 2% for epic swarm.
Rewards are based on gained score and swarm size (for common talismans). Only successfully cleared swarms give any swarm rewards, failed give nothing, not even the score based.
Common talisman type is based on the area.
You get all rewards you have the points for, e.g. if you get 500 points, you get the common talisman(s), 1 Portal Orb, both blessings, 5 additional fragments and the town materials.
You always get the common talisman reward if you clear the swarm.
Town materials are based on swarm area.
Uncommon talisman type is always that of active hero. It doesn’t matter who clears how much of the swarm.
The basic scoring is 1*difficulty per clear, 10 per mutant and 10 per every full minute left.
These numbers are multiplied by 1.2 with 1900 area missions or by 1.5 with 2900 area missions. The former can be seen on the screenshot with rewards.
Total area clear count during the swarm is used for the score. Clears above the swarm clear threshold still count for score. Sometimes, a character can get additional area clears when the swarm clear requirement is met. Passive characters provide less clears based on their background efficiency.
Each monster has a 1*difficulty in 4000 chance of being a mutant. Mutants have higher stats, bigger sprite and give additional 10 points to the swarm. Passive characters mutant rewards are again multiplied by background efficiency.
Early game guide
Swarms can be detrimental because they can prevent you from clearing an area you normally can clear. You can save and reload in this case or just wait it out.
Any swarm will lower clear speed of its area. However, it can significantly increase gold/exp/resource/monster material gains. A swarm can be worth farming when you can’t clear it, sometimes even when you can’t clear the area itself with the swarm. It is a trade off between clear counts/town materials and monster drops – consider what you need and act accordingly.
The key to properly using the swarm is getting as many monsters defeated per second as you can. This means piercing and/or high AoE skills. Early on, these will be wing shoot, wing attack (fast, can hit multiple targets), swing around, meteor strike etc. Archer has multiple good skills (piercing arrow and frozen arrow come to mind).
If you can clear swarms, always do it. Swarm chaser is very helpful if you have it.
Late game score chase
Past early game, swarm clearing becomes a routine, the timer is just a score bonus and I assume you already have swarm chaser. Sooner or later, you will want the swarm talismans. I’ll focus on tracker’s map, enchanted alembic will be gained along the way.
The “easiest way” to get more tracker’s maps is to either get all swarms epic or have a very high area clear count multiplier. The only problem is that you need tracker’s maps first for both of these.
The math is simple – you want guaranteed 3000 points for every swarm. Certain area mission milestones (1900, 2900) are very helpful. You don’t strictly need them, but they make everything easier. Don’t expect passively farming tracker’s maps without either these milestones or a stack of tracker’s maps.
You can actively gain points without getting clears by farming mutants. This works best in a high difficulty area (you want many waves and high mutant spawn rate) – switch between 2 difficulties before you get a clear. Once you have enough points from mutants, let the swarm get cleared. You might want to disable swarm chaser first and to prepare many areas where you can do that. I don’t think more than 1 full map stack from this is needed. Difficulty 4/5
Passive tracker’s map farming is based on getting 3000 points from swarms without having to do anything. Mutants aren’t involved. Just get enough points from area clears to get there.
Area optimization for 3000 point swarms
Focus on swarm chasing can be at the expense of some other progress, This won’t be a problem with enough tracker’s maps already gained, but you need to get there first.
Exact numbers depend on area milestones, talismans and clear multiplier. Go for quantity over quality – there’s no difference between 3k and 30k points, but there’s a big difference between 20 and 30 areas that will get you the map.
First consider who and how clears the swarm. You should expect first area clear to clear any regular swarm and maybe larges as well. You might want the active to have the highest clear speed to always get the full number of clears and prestige the areas for this alone.
Clear count per clear is based on 3 things – area booster, tracker’s map and exporer’s boon of the swarming area. Area booster and tracker’s map are additive with each other. Total clear count*difficulty should be at least 1710/2210/2710 (for 2900/1900/less area missions), assuming 1 minute clear and not depending on mutants. Passives getting the first clear get their background (in)efficiency multiplier.
Available swarm types can significantly alter the math. If you get many regular swarms, you should focus on a single clear getting 3000 points. If you get mostly large swarms, having 2 passive chars getting a bit under 150 clears will guarantee close to 300 clears (make sure active won’t get a clear, being in a dungeon or porbing), getting maps easily. Epic only guarantees at least 300 clears per swarm (and at least 3135 points on a diff 6 area with 2900 missions). I don’t consider epic only there, you don’t need this guide by then.
The biggest problem is getting the first map stacks to increase clear counts. If you get 2900 area missions and lv 100 area booster, you can just start getting areas to diff 10, level 10 boon and wait for the maps to come (make sure active clears them). Any already present maps can make you lower the difficulty/boon.
If you get 1900 area missions, you need some maps first (farm mutants or something). Otherwise you can’t get the 111 booster+map clears needed to guarantee 3k points with diff 10, boon 10. If you have a high large swarm spawn chance, you can use a passives only approach (134 – 136 clears per clear or 201-272 clears range, these numbers include boon and are based on 55% efficiency). You need 74 clears for 3 clears or 111 – 149 for 2 clears to get 3000 points.
If you have less than 1900 missions, it gets even more complicated and you will be better off just getting them first (124 -136 base clears and a large swarm on 2 passives or 136 base clears on active needed for diff10 boon 10 map).