Description
This is a little mod (based on the original The Summoner by Daveyx0) revolving around a mob called the Summoner. You might recognize him as an Illager and his name probably gives away what he does. There is more to him than you think however. Continue below for more info.
This mod is still in beta! (7 years later and it's still in beta lol, But it's fully functional.)
The Summoner
These guys spawn like any other mob but are a bit more uncommon. They attack players, villagers and iron golems on sight. As you might have guessed they spawn a group of mobs to fight for them!
Here you see a Summoner summoning some skeletons to attack an Iron Golem. See the purple around the Summoner? This means he is invulnerable to attacks! He puts up that shield when casting summons and it lasts a few seconds before it ends. He will keep spawning new summons on a cooldown; however the summons only stay alive for 1800 ticks before they automatically die. (Yes, their summons are somewhat similar to Horcruxes.)
If you manage to kill a Summoner; their summons will death before their time limit is up (but technically it's impossible for that to happen, since everyone must be dead for their shield to lower, only if you change the game mode to peaceful It's the only possibility). The Summons do not drop anything; however the Summoner drops a Summoner Orb and possibly some Emeralds.
The Summoner Orb
Summoner drop these 50%. They can be used to capture spirits/soul of any mob! (Mobs in blacklisted are the wither and the dragon). While you have one in your inventory there is always chance a spirit of a mob you kill is captured in the orb. The chance is dependent on the mob's health. A mob with 20 health will have a 1/20 chance of being captured on death. Once captured; you can right click with the orb to summon the mob as your follower.
This zombie is the follower of the player you see here. They follow you and attack whatever you attack. You will notice that spawning the mob costs durability for the orb. An orb has limited uses but can be repaired with an exp bottles or totems. You can shift and right-click the mob with the orb to make them retreat. The mob will also retreat when they die.(they also don't despawn).
Not happy with the mob you captured? Simply put the orb in a crafting grid and you can reset it's contents.
Time to make an army!
The Summoner Overlord (Boss)
Right-clicking a Summoner with an Eye of Ender start a mini-boss fight that can actually be pretty tough. The Summoner Boss has 10 waves of enemies that he throws at you; during that time he is invulnerable to any attack! Defeat the waves to make him vulnerable again. Be careful though, the boss no can despawn when you die! So make sure you are prepared or you might not get a second chance. It's a decent challenge with a fun reward. 
The Boss drops an Summoner Orb Powered, as well as multiple Emeralds.
The Summoner Orb Powered
Works the exact same as a normal orb; but it is indestructible (infinite durability, immune to burning and explosions)
Some questions and answers:
Why isn't this guy part of Primitive Mobs?
- The original creator of the mod, Daveyx0, separated it from Primitive Mobs a long time ago. Primitive Mobs received a port for more recent versions, but the Summoner did not, so I decided to take care of it since it was my second favorite mob from Primitive Mobs.
Is Multi Mob library no longer necessary?
- No, Although perhaps in the future I'll have to do something similar to be able to handle the auras of the summons, for now they use the glowing effect
-Will the summoner have any redesign or any changes to its model or texture?
Yes, these are my ideas for the regular summoner and the boss.
They're a mix of the original summoner design from 1.7, the 1.12.2 redesign, and the multi-mob library mage; in addition to referencing the warlock from my Magnificents Mobs addon
Known issues:
- If your summon dies and you don't have its orb in your inventory, you won't be able to recover it.
- The summoner's arm animation when summoning is bugged (I'm working on an improved model and texture, but for now I'm using the original).
-For now, none of the mod settings are editable.
New Features:
- Unlike the original mod, if a summon disappears due to peaceful mode, in this new version it will return to its orb so you don't lose it.
- Improved compatibility with creatures from other mods and new Minecraft entities that use a different targeting system (such as piglins or wardens).
-It can spawn in raids.
Planned Features:
- A new villager with a Friendly Summoner profession that sells orbs containing mobs to summon
- Balance changes
-Add/revert more features of the original mod that I modified while testing
- Many bug fixes once the bugs arise :^)
- The ability to craft an orb together with a Sword to imbue it with a "Bane" towards that mob, meaning it will deal double damage to them.
Disclaimer: The original mod's source code is public and was created under a Creative Commons Attribution-NonCommercial license, which grants permission to distribute and publicly perform an adaptation.
According to (Section 1a): The text defines "Adaptation" as a work based on the original work, including alterations, transformations, or recodings.