Lineages give you the ability to unlock and choose new upgrades related to the Bloodline you're using, and will even give access to the faction spell of the bloodlines origin at later stages. They also bring with them a whole set of allegiance trophies for all 12 factions.
Requirements
 R60+
 Lineage can't match current faction
 400 royal exchanges of the respective faction(s) (two FC types for neutrals)
 Bloodline of the respective faction
 You have to also take a prestige faction
The requirements need to be fulfilled each abdication.
If you purchase research A2950 prior to selecting your bloodline's lineage, you will be able to choose which of the two bloodlines is the primary lineage and gain access to their spell (if unlocked).
e.g. Mercenary faction with dragon bloodline purchases A2950 and selects the druid bloodline. The player can choose between the two bloodline's lineages (dragon or druid) if they have not already done so.
Progression Edit
Level 5: Perk 1
Level 10: 100x FC gain for the lineages respective faction (50x for each of the two neutral FC types)
Level 15: Perk 2  Unlocks Faction spell. (adjusted for your alignment if necessary)
Level 20: Perk 3 + Grand Champion Trophy
Level 30 (PA2): Perk 4  boosts faction spell
Costs Edit
The base cost for upgrading lineages is 25 Qa (2.5_{E}16) Faction Coins, and it increases by 10x per level (7.94x with Ancient Heirloom lore artifact). Note that the heirloom bonus will only apply to lineages below your highest level lineage
Formula: $ 2.5e(15+level) $NOTE: Levels only have to be purchased once, and are retained between reincarnations
Formula: $ (2.5e(15+level))^{0.9} $ (with heirloom)
Costs per level  

Level  Normal  Heirloom  Level  Normal  Heirloom  
1  25 Qa (2.5_{E}16)  573 T (5.73_{E}14)  11  250 Sp (2.5_{E}26)  573 Sx (5.73_{E}23)  
2  250 Qa (2.5_{E}17)  4 Qa (4.55_{E}15)  12  2 Oc (2.5_{E}27)  4 Sp (4.55_{E}24)  
3  2 Qi (2.5_{E}18)  36 Qa (3.62_{E}16)  13  25 Oc (2.5_{E}28)  36 Sp (3.62_{E}25)  
4  25 Qi (2.5_{E}19)  287 Qa (2.87_{E}17)  14  250 Oc (2.5_{E}29)  287 Sp (2.87_{E}26)  
5  250 Qi (2.5_{E}20)  2 Qi (2.28_{E}18)  15  2 No (2.5_{E}30)  2 Oc (2.28_{E}27)  
6  2 Sx (2.5_{E}21)  18 Qi (1.81_{E}19)  16  25 No (2.5_{E}31)  18 Oc (1.81_{E}28)  
7  25 Sx (2.5_{E}22)  144 Qi (1.44_{E}20)  17  250 No (2.5_{E}32)  144 Oc (1.44_{E}29)  
8  250 Sx (2.5_{E}23)  1 Sx (1.14_{E}21)  18  2 Dc (2.5_{E}33)  1 No (1.14_{E}30)  
9  2 Sp (2.5_{E}24)  9 Sx (9.08_{E}21)  19  25 Dc (2.5_{E}34)  9 No (9.08_{E}30)  
10  25 Sp (2.5_{E}25)  72 Sx (7.21_{E}22)  20  250 Dc (2.5_{E}35)  72 No (7.21_{E}31) 
Perks Edit
Perk 2 Challenges List  

Fairy  Reach 2000 assistants in less than 10 minutes 
Elf  7777 autoclicks in the first 5 minutes of a run. 
Angel  Have at least 8 hours of time with at least one spell active this game and at most 8 hours 1 minute of playtime this game. Spell time does not need to be continuous. 
Goblin  Cast 1 million Tax Collections in a single game 
Undead  Have Night Time's spell duration be 60 seconds. 
Demon  10 days of Hellfire Blast activity time (This R). 
Titan  25,000 mana per second as pure Titan (no dragons, BL doesn't matter) 
Druid  Have a mana regeneration of at least double your max mana 
Faceless  Cast 100 Brainwaves in a single game 
Dwarven  Have 10,000 Excavations 
Drow  30 days offline across all Reincarnations 
Dragon  Cast 5 spells at Tier 5 in less than 10 minutes 
Unlock Builds Edit
Main page: Merc Builds
Credit to G00FBALL for finding and formulating the info. Original source can be found here
Realm Grinder 

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