After Fire Prism Assault, there are four missions:
- Calderis (3 foundries) - Hand of the Hive Mind, The Killer Serpent
- Typhon (1 foundry) - Green Armor
- Meridian (1 foundry) - Lord of Wraiths
We chose The Killer Serpent first to get another Shrine. The Hand of The Hive Mind mission has a Communications Array, which is less urgent.
Mission 12 The Killer Serpent
- Day 8, Fury 5, Resilience 5, Speed 3 (17 minutes; Speed 5 for completing in 10 minutes on Normal difficulty). Two extra deployments awarded.
- Infestation: Calderis 5 (3 after mission), Typhon 5, Meridian 0
- Where they are hidden can be located in hiding by the small crater/circle of cracked earth on the ground. If you sneak up on them, sometimes you can hear a squishy sound which is the Ravener tunneling into the ground.
- Any attack directed at the crater should cause it to reveal. This generally requires an area effect attack, such as a grenade or Flamer (using the Attack Ground command).
- The attack you use will inflict damage as normal.
- You can use Thaddeus' Assault Jump but it seems that the Ravener erupts before the jump is completed, causing damage before Thaddeus' invulnerability from Aegis of Fury kicks in.
- A Detonation Charge Pack can kill it without it even revealing itself (?).
- When it emerges from the ground, the shockwave is quite wide but damage falls of quickly. Damage to buildings and any squads garrisoned in a building seems to be very great (on Primarch Difficulty).
- While hidden, it can detect Infiltrated units although it might not reveal itself.
- At this early stage of the game, a Ravener in melee (on Primarch difficulty) is extremely dangerous. If you have Cyrus, a High-Powered Shot will kill one right away.
- The Ravener Alpha / boss Ravener
- Can be drawn out of hiding like other Raveners.
- You know where it is approximately because it is a quest objective and marked on your mini-map. If there isn't a mission-critical structure there, it must be the Ravener.
- The area might not be marked by a crater as the Ravener Alpha can move around. Look at the mini-map to determine where to lob a grenade.
- If grenades won't make it appear, the safest character with which to draw it out is the Force Commander, as on Primarch, he will lose about half his health. Most other squads typically lose all squad members and a dangerous amount of squad leader health.
- The Hive Nodes are best taken out with Cyrus's Detonation Charge Packs -- throw it and run unless you have Advanced Infiltrate If there is a Tyranid Warrior nearby, snipe it first to stun nearby Tyranids so that you can more comfortably escape. Otherwise, usually a Retreat is required to escape a spore launch.
- When Tyranids kill each other because one group has lost its Tyranid Warrior and becomes detected as hostile, those kills do not count as your kills, so you lose kill percentages toward Fury stars.
- After this mission, if you complete Hand of the Hive Mind with the extra deployment and further reduce the infestation on Calderis by 3, you could reduce infestation to 0 until the next day. However, nothing special happens for having reached infestation level 0 even momentarily.