I love what you've done with the slivers, I must say they look good. I am not sure what custom ones you had planned, but here are a few I put together, not to the same style as yours but I though they were good when I made them. feel free to improve them though. I think these could add some real flavor to the mix, though they were all done before the Legions and Scourge Sliver's came out.
Your work seems a lot better written then mine though, so I take no offence if these ones suck in comparison.
Non Standard Slivers
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Beacon Sliver
Large Aberration
HD: 2d8 + 8 (hp: 17)
Initiative: +3 (+1 Dex, +2 Queen Control)
Speed: 30ft.
AC: 13 (-1 size, +4 natural)
Attacks: claw +4 melee, 2 Tails +4 melee.
Damage: claw 1d8+2
Face/Reach: 5ft. x 10 ft./5 ft.
Special Attacks: Nil
Special Qualities: Beacon Aura , psionics, Queen control.
Saves: Fort +4, Ref +1, Will +3
Abilities: Str 14, Dex 12, Con 18, Int 3, Wis 10, Cha 10
Skills: Climb +10, Hide +4, Listen +7, Spot +7
Feats: Alertness
CR: 2
Alignment: Always Lawful Neutral
Advancement: 3-4 HD (Large), 5-6 HD (Huge)
Special Qualities:
Beacon Aura(Su): All Slivers within 40ft of a Beacon Sliver (including itself) gain a +20 ft bonus to their Aura Ranges and Gain a Complete Link to the Queen, No matter how far away from her they are. These bonuses are not included in the statistics presented above (so, effectively, a Beacon Sliver has a ).
Psionics(Su): The Beacon Sliver can detect thoughts at will. As all Slivers, a Beacon Sliver is innately telepathic, and in constant communication with any nearby Slivers. This means that as long as a single Sliver is aware of a situation or event, all others in the same plane are automaticaly aware as well (so, no such thing as surprised Slivers).
Queen Control(Su): Like all Slivers, the Beacon Sliver is under the direct control of the brood's Queen. In effect, the Queen knows and directs the actions of all the Slivers in the brood. This coordination grants a +2 insight bonus to all Sliver Initiative checks (but not to the Queen's).
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Chameleon Sliver
Large Aberration
HD: 2d8 + 8 (hp: 17)
Initiative: +3 (+1 Dex, +2 Queen Control)
Speed: 30ft.
AC: 13 (-1 size, +4 natural)
Attacks: claw +4 melee, 2 Tails +4 melee.
Damage: claw 1d8+2
Face/Reach: 5ft. x 10 ft./5 ft.
Special Attacks: Nil
Special Qualities: Chameleon Aura , psionics, Queen control.
Saves: Fort +4, Ref +1, Will +3
Abilities: Str 14, Dex 12, Con 18, Int 3, Wis 10, Cha 10
Skills: Climb +10, Hide +4, Listen +7, Spot +7
Feats: Alertness
CR: 2
Alignment: Always Lawful Neutral
Advancement: 3-4 HD (Large), 5-6 HD (Huge)
Special Qualities:
Chameleon Aura(Su): All Slivers within 30ft of a Chameleon Sliver (including itself) gain Camoflague ability, Giving them +8 to Hide, And making them Semi Invisible to sight based senses (Non-Magic, 25% Miss chance). These bonuses are not included in the statistics presented above (so, effectively, a Chameleon Sliver has ).
Psionics(Su): The Chameleon Sliver can detect thoughts at will. As all Slivers, a Chameleon Sliver is innately telepathic, and in constant communication with any nearby Slivers. This means that as long as a single Sliver is aware of a situation or event, all others in the same plane are automaticaly aware as well (so, no such thing as surprised Slivers).
Queen Control(Su): Like all Slivers, the Chameleon Sliver is under the direct control of the brood's Queen. In effect, the Queen knows and directs the actions of all the Slivers in the brood. This coordination grants a +2 insight bonus to all Sliver Initiative checks (but not to the Queen's).
Created by outside forces this Sliver is usually not found in the Hive Hierarchy, though it can easily be intigrated if brought to the Queen. Once presented to the Queen it takes a day to Bond, then the Chameleon Sliver is a full Member of the Hive.
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The Scorpion Slivers Dwell in Desert Environments, and Look similar to Giant Scorpions, they have developed an Additional Claw and their tails have transformed into a Large Scorpion Stinger. From a distance they are often mistaken for Giant Scorpions, much to the Loss of the Viewer.
Scorpion Sliver
Large Aberration
HD: 6d8 + (hp: 17)
Initiative: +1 (+1 Dex, +2 if under the effect of Queen Control)
Speed: 30ft, Borrow 20'.
AC: 18 (-1 size, +6 natural, +3 Dex)
Attacks: 2 Claws +6 melee, Stringer Strike +6 melee.
Damage: Claw 2d4+2, Stinger Strike 2d6+2+Poison
Face/Reach: 5ft. x 10 ft./10 ft.
Special Attacks: Stinger Poison
Special Qualities: Tremor Sense, Scorpion Aura , psionics, (Optional) Queen control.
Saves: Fort +4, Ref +3, Will +3
Abilities: Str 16, Dex 16, Con 18, Int 3, Wis 10, Cha 10
Skills: Climb +8, Hide +6, Listen +7, Spot +7
Feats: Alertness
CR: 5
Alignment: Always Lawful Neutral
Advancement: 7-8 HD (Large), 9-10 HD (Huge)
Special Attacks:
Stinger Poison- Same as the Poison that the Aura gives to other Slivers, though DC's are 2 pts higher
Special Qualities:
Tremor Sense(Ex):While resting under the sand Scorpion Slivers can sense any creature or movement across the Sand within 200' of their position. They only know general size, location of the creature and direction of movement.
Scorpion Aura(Su): All other Slivers within 30ft of a Scorpion Sliver gain +4 to their Natural AC (due to Chitinous Material), Their Tails Merge together forming a Large Stinger. This Stinger that deals 2d6+Str Mod, and injects a Paralytic poison, onset time-Immediate, (DC 16) that causes the victim to Twitch on the ground for 1d16 rounds. Secondary Save- (Dc 18) Lose 1d6 Strength Points temporarily.
Psionics(Su): The Scorpion Sliver can detect thoughts at will. As all Slivers, a Scorpion Sliver is innately telepathic, and in constant communication with any nearby Slivers. This means that as long as a single Sliver is aware of a situation or event, all others in the same 1 mile area are automaticaly aware as well (so, no such thing as surprised Slivers).
Queen Control(Su): Unlike all other Slivers the Scorpion Sliver is usually found outside the Hive Environment as they were created by a Insane mages experiments, Though if brought to the Queen They act just like other Sliver the Scorpion Sliver is under the direct control of the brood's Queen. The Queen Only knows and directs the actions of the Scorpion Sliver if it has binded with her. Once Bonded This coordination grants a +2 insight bonus to all Sliver Initiative checks of the Scorpion Sliver.
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Jolt Sliver
Large Aberration
HD: 2d8 + 8 (hp: 17)
Initiative: +5 (+3 Dex, +2 Queen Control)
Speed: 30ft.
AC: 16 (-1 size, +4 natural, +3 Dex)
Attacks: claw +4 melee
Damage: claw 1d8+2
Face/Reach: 5ft. x 10 ft./5 ft.
Special Attacks: Nil
Special Qualities: Jolt Aura , psionics, Queen control.
Saves: Fort +4, Ref +1, Will +3
Abilities: Str 14, Dex 16, Con 18, Int 3, Wis 10, Cha 10
Skills: Climb +10, Hide +4, Listen +7, Spot +7
Feats: Alertness
CR: 2
Alignment: Always Lawful Neutral
Advancement: 3-4 HD (Large), 5-6 HD (Huge)
Special Attack:Spring Attack-Exactly like the Feat of the Same Name. Page 85 of PHB.
Special Qualities:
Jolt Aura(Su): All Slivers within 30ft of a Jolt Sliver (including itself) gain a +2 enhancement bonus to their Dexterity and Initiative, they gain the feat: Spring Attack, even if all the Prerequisites are not met . These bonuses are not included in the statistics presented above (so, effectively, a Jolt Sliver has 18 Dex, 17 AC, and +8 Init).
Psionics(Su): The Jolt Sliver can detect thoughts at will. As all Slivers, a Jolt Sliver is innately telepathic, and in constant communication with any nearby Slivers. This means that as long as a single Sliver is aware of a situation or event, all others in the same plane are automaticaly aware as well (so, no such thing as surprised Slivers).
Queen Control(Su): Like all Slivers, the Jolt Sliver is under the direct control of the brood's Queen. In effect, the Queen knows and directs the actions of all the Slivers in the brood. This coordination grants a +2 insight bonus to all Sliver Initiative checks (but not to the Queen's).
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Taskmaster Sliver
Large Aberration
HD: 4d8+12 (hp: 30)
Initiative: +5 (+3 Dex, +2 Queen Control)
Speed: 30 ft.
AC: 16 (-1 Size, +3 Dex, +4 natural)
Attacks: claw +4 melee
Damage: claw 1d8+1
Face/Reach: 5ft.x10ft./5ft.
Special Attacks: Nil
Special Qualities: Taskmaster Aura, Psionics, Queen Control
Saves: Fort +3, Ref +3, Will +3
Abilities: Str12, Dex16, Con16, Int12, Wis10, Cha15
Skills: Climb +10, Hide +7, Listen +7, Spot +7
Feats: Skill focus: Hide
CR: 4
Alignment: Always lawful neutral
Taskmaster Aura(Su): All slivers within 30 ft. of a Taskmaster Sliver are animated as skeletons under the Taskmaster's control when they die. Any sliver corpses brought to within 30 ft. of the Taskmaster are also animated. Any slivers leaving the 30 ft. area remain animated, but are uncontrolled. NOTE: Skeleton Slivers no longer give nor recieve aura bonuses from other slivers. Also a Taskmaster's Aura does not animate the Taskmaster when it dies (as it's aura stops).
Psionics(Su): The Taskmaster Sliver can detect thoughts at will. As all Slivers, a Taskmaster Sliver is innately telepathic, and in constant communication with any nearby Slivers. This means that as long as a single Sliver is aware of a situation or event, all others in the same plane are automaticaly aware as well (so, no such thing as surprised Slivers).
Queen Control(Su): Like all Slivers, the Taskmaster Sliver is under the direct control of the brood's Queen. In effect, the Queen knows and directs the actions of all the Slivers in the brood. This coordination grants a +2 insight bonus to all Sliver Initiative checks (but not to the Queen's).
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Razor Sliver
Large Aberration
HD: 2d8+2 (11 hp)
Initiative: +5 (+3 Dex, +2 Queen Control)
Speed: 30 ft.
AC: 16 (-1 Size, +3 Dex, +4 natural)
Attacks: claw +4 melee
Damage: claw 1d8+2
Face/Reach: 5ft.x10ft./5ft.
Special Attacks: Nil
Special Qualities: Razor Aura, Psionics, Queen Control
Saves: Fort +1, Ref +3, Will +3
Abilities: Str14, Dex16, Con12, Int03, Wis10, Cha10
Skills: Listen +3, Spot +3
Feats: Weapon Focus: Claw
CR: 2
Alignment: Always lawful neutral
Razor Aura(Su): All slivers within 30 ft. of a Razor Sliver (including the Sliver itself) gain the wounding special power on their claw. Each attack from their claw inflicts a terrible wound that continues to bleed for 1 hp of damage each round until either a Heal check (dc 15) or curative magic (any) is applied. This is not figured into the sliver's stats above.
Psionics(Su): The Razor Sliver can detect thoughts at will. As all Slivers, a Stinging Sliver is innately telepathic, and in constant communication with any nearby Slivers. This means that as long as a single Sliver is aware of a situation or event, all others in the same plane are automaticaly aware as well (so, no such thing as surprised Slivers).
Queen Control(Su): Like all Slivers, the Razor Sliver is under the direct control of the brood's Queen. In effect, the Queen knows and directs the actions of all the Slivers in the brood. This coordination grants a +2 insight bonus to all Sliver Initiative checks (but not to the Queen's).