YMMV / Empires of the Undergrowth

• Checkpoint Starvation: You cannot save during story mode missions. Although most of the missions don't get pass 1 hour of play time if you know what you are doing, many players are annoyed that their progress can be ruined by one small mistake or random crashes near the end.
• Demonic Spiders: Not only spiders but many other creatures can also be considered demonic in this game. The adults are immune to common status effects, have nasty abilities and come in swarms.
  • Tiger beetles are fast and strong with powerful area of effect stun. A few adults together can stun lock you.
  • Wolf spiders are even faster and stronger, with the ability to run pass your defense into a random brood chamber. You are most likely to lose when they inject venom into your queen.
  • Praying mantises are annoyingly tanky with the ability to regain health constantly by eating your ants. They even got requested to be nerfed by insane difficulty players.
  • Spiny crickets can reflect melee damage and cause enemies to bleed. A few adults can devastate your entire army very quickly.
• Difficulty Spike: Missions 3.x and 4.x both fit the bill.
  • 3.x features a totally new variety of ant that can't eat any source of food except the fungi it creates from leaves, meaning you can't recoup loses from slain enemies. The Army Ants in 3.2 are also an absolute pain to fight, especially if you don't have the numbers to cut off a line.
  • 4.x introduces amphibian enemies, all of which have to ability to heal themselves by eating your ants and get increased healing duration the more ants they eat.
• Game-Breaker:
  • Two of the gene thief queen's additional abilities are overpowering and give your colony Nigh-Invulnerability when the queen reaches 75% in health. Royal Decree makes every unhatched ant in the colony instantly spawn and hatch for free for 20 seconds, giving you an infinite army for the duration. Second Wind heals the Queen completely and makes her outright invulnerable for 30 seconds. Their only weak point is the long cooldown but as long as the colony can hold on long enough, these abilities can be activated again.
  • The spiders in mission 2.1 are designed to target your chambers before heading for the queen when they enter your nest. Building one-tile chambers in various corners in your nest can help spread the spiders thin, allowing you to pick on them one by one.
  • Level 3 mortar shooters are overpowering with their area of effect damage. Many missions with mortar shooters available can be easily cheesed by camping the enemies spawn point or your nest entrance. Area of affect damage was later change to splash damage for balance.
  • In mission 3.2, you have to kill a certain number of army ants yourself to deplete the progress bar. However, on harder difficulty, army ants can be devastated by randomly crossing praying mantises without lowering the progress bar, making the level impossible to beat. You can trigger the scouts that occasionally wander the empty lanes, letting them call for more army ants for you to kill.
• Goddamned Bats: Harvestmen drop only a small amount of food but take so much time to kill. They can constantly stun multiple ants at once, preventing you from doing any damage and even if you do, they will drop a leg as distraction and run away.
• Nightmare Fuel: It's pretty much expected in a game about insects.
  • Spiders Are Scary: Arachnid species have more advance abilities and smarter AI than other creatures, making them even more terrifying to face. There are also holiday missions featuring a wolf spider as main character with a really creepy voice.
  • The narrator makes familiar and mundane insects sound like terrifying monsters through his poetic descriptions.
  • The male scientist's obsession with the gene thief ants seems to imply that he has more nefarious plans for them in the future challenges.
  • Formica ereptor can assimilate DNA from other species and breed various adaptable soldiers of their own. If they have a chance to escape, it would be a natural disaster as they will out-compete any local ant species, conquering the entire undergrowth by themselves.
• I Knew It!: On the topic of ants included as complete species in the game, many fans posited that the final species would be either driver ants or matabele ants. Matabele ants seemed to be more likely after John's revelation of Flashheal ability. After the hilarious leaks during Liam's stream, they have confirmed that matabele ants would be the playable species and driver ants would be their enemies in the 5th set of missions.
• Retroactive Recognition: You may be surprised to hear MauLer narrating about ants
• That One Level:
  • Mission 3.1 is difficult if you don't know efficient nest designs and where to harvest first. It's telling that the mission has multiple threads on the Slug Disco and Steam Forums just for completing it on medium.
  • In mission 3.2, on hard and insane, the number of creatures is so ridiculous that you can't harvest safely at night and they even kill the army ants themselves without dropping the progress bar during the day, forcing players to quit. Many high level players requested a nerf for creatures spawn rate on insane, especially the praying mantises.
  • Formicarium challenge 3 is extremely hard if you don't unlock additional ability or increase your ants' stats, even on easy. You have to face an opposing gene thief colony with slavemaker soldiers, trapjaw ants, army ant medias and majors, which are all stronger than black ants. You have to also avoid being killed by the scientist himself. Many players are discourage by the need of grinding for more food and royal jelly to beat this challenge, or how mortar shooters can trivialize it, making it unfair for those not knowing. On the other hand, some players have even beaten this on insane without any additional abilities and stat buffs.
• Unexpected Character: Zigzagged - it was generally assumed that Matabele Ants would be the final playable species, which was eventually confirmed after a leak during Liam's stream. When the trailer revealing the ants' environment and their termite foes was revealed, though, players were surprised to see that, in addition to having a healing attack, the game would include the Matabele's signature trait of bringing wounded ants back to the nest for healing, in part because there had been no mechanic to recover your own losses up until this point.