College of sigils

You’re education as a bard was non traditional to say the least. Using symbols or sigils to inspire and bolster your allies. with this subclass you are able to Bolster and later curse yourself and manifest your drawn sigils on other creatures. Additionally you can summon an aspect of a sealed power to aid you. 

Sigils of support

You create sigils of support as a bonus action and it uses one use of bardic inspiration with one of five types effecting you and an ally within 30ft at a time: healing, defense, attack, resistance, and speed

these effects last 1 hour or until you use another sigil

sigil of healing heals you and an ally for 2d4+ your bard level can be done a number of times equal to your proficiency plus your charisma modifier before your sigil disappears (Requires a bonus action)

sigil of defense gives you and one ally + 2 to ac

sigil of attack gives you and one ally + 2 to attack and damage rolls 

sigil of resistance gives you and one ally one of the following benefits: resistance to magical and nonmagical damage of one type, resistance to non magical damage, or advantage on saving throws caused by magical effects

sigil of speed gives you and one ally + 10ft of movement 

Sealed Assistant

As a crafter of seals and sigils you can use your power to gain the companionship of a magical creature of cr equal to 1/4th of your level

you may choose a fiend, celestial, or dragon

Sigil of negativity

At 6th level you can craft new seals which are meant to harm a target within 30ft: harm, vulnerability, lethargy, feebleness, rust.
Additionally you can only have one sigil of negativity active but can have a sigil of support active at the same time as a sigil of negativity.

harm: you and a target take 3d6+your bard level necrotic damage

vulnerability: you and a target become vulnerable to one damage type or have disadvantage on spell saves from magical effects

lethargy:you and a targets speed are halved and you each can only make one attack per turn

Feebleness: you and a target have -1d4 to attack and damage rolls

rust: you and a target have -2 to ac

Crafter of seals

You now have deep understanding of arcane seals and sigils you can now attempt to craft your own

it takes one hour to craft a new arcane sigil which can be done during a short rest and cost 10gp plus 10gp per level of spell in incense to craft these sigils for the first time and after you have crafted it it is added to your known seals and requires no additional components and takes a bonus action to drawl

it must affect you and may affect one other person with 30ft in the same way

these can be in the form spells or an effect agreed upon effect

Master of sigils

At 14th level you can affect more than one other creature with your sigils and your sigils double in power

When you use a sigil you can affect yourself and 2 other creatures 

3 times per long rest: when you use a sigil you may have the effects of it double effect it has on any one creature effected by it. ie: Target vulnerability is quadrupled not just doubled or target heals for 2d4 plus your bard level times 2