It's possible my biases are showing with this character - a Tytalus Diedne.
Characteristics: Int +2, Per +1, Pre +1, Com +3, Str -1, Sta +0, Dex -2, Qik +0
Size: 0
Age: 25
Decrepitude: 0
Warping Score: 0 (0)
Confidence Score: 2 (5)
Virtues and Flaws: The Gift; Hermetic Magus; Diedne Magic; Good Teacher, Inspirational, Magical Memory, Puissant Intrigue, Quiet Magic, Self-Confident*, Skilled Parens, Subtle Magic; Dark Secret**, Driven (get Order to destroy itself), Rigid Magic, Twilight Prone; Prohibition (cannot betray the Diedne)
*House Virtue
**Free from Diedne Magic
Personality Traits: Determined to stoke intra-Order strife +6, Twisty +3, Superficially pleasant +2
Reputations: None
Combat:
Dodging: Init 0, Atk n/a, Dfn +2, Dam n/a
Soak: +0
Fatigue Penalties: OK, 0, -1, -3, -5, Unconscious
Wound Penalties: -1 (1-5), -3 (6-10), -5 (11-15), Incapacitated (16-20)
Abilities: Artes Liberales 2 (rhetoric), Athletics 1 (running), Awareness 1 (guards), Brawl 1 (dodging), Charm 1 (rhetoric), Code of Hermes 1 (tribunals), Concentration 1 (spells), Folk Ken 1 (rhetoric), Guile 3 (elaborate lies), Intrigue 4+2 (rumourmongering), Latin 5 (Hermetic terms), Leadership 2 (rhetoric), Magic Theory 3 (inventing spells), Native Language 5 (insults), Order of Hermes Lore 2 (political factions), Parma Magica 1 (Mentem), Stealth 1 (shadowing)
Arts: Cr 5, In 8, Mu 3, Pe 4 Re 0, An 0, Aq 6, Au 0, Co 0, He 0, Ig 0, Im 8, Me 5, Te 0, Vi 3
Twilight scars: None
Equipment: Wizardly robes
Encumbrance: 0 (0)
Spells known:
Mighty Torrent of Water (CrAq 20) +11
Summoning the Distant Image (InIm 25) +16
Wizard's Sidestep (ReIm 10) +8
Aura of Enobled Presence (MuIm 10) +11
Veil of Invisibility (PeIm 20) +12
Rising Ire (CrMe 15) +10
Trust of Childlike Faith (PeMe 10) +9
Loss of But a Moment's Memory (PeMe 15) +9
The Call to Slumber (ReMe 10) +5
Shroud Magic (MuVi 15) +6
Character Notes
During the Schism War, a Tytalus magus took the apprentice of a Diedne magis he had slain as their own. Exactly why he did this is unclear; simply taking the spoils of a victory, challenging himself to turn them to the Order or believing it would be a good test of the Order's ability to cope with traitors in its midst have all been suggested. Whatever the reason, the result has been a small lineage of Diedne within House Tytalus devoted to the Order's destruction.
As a young apprentice, this character was inducted into the mysteries of Diedne magic and sworn to secrecy and loyalty with terrible oaths. Now they seek to provoke the Order to tear itself apart by fanning divisions and promoting enmity amongst its members - all under the pretext that the resulting conflicts will help the Order grow stronger.
Customisation Notes
The character has its full complement of Virtues and Flaws; however, Inspirational, Good Teacher or Magical Memory could be swapped out at the cost of making the character less good a demogoguery or easier for an outsider to investigate their projects. A second level of Quiet Magic would be particularly useful.
As it stands, the character is very much politically focussed, so would work best in a saga emphasising Hermetic politics, although they have some general skill at sneakiness and information gathering. They have very little penetration on most of their spells, which means that they would be ill advised to cast them on magi; their grogs are fair game (as long as they don't get caught), but note that the character's key aim is to provoke trouble amongst other magi rather than risk getting into trouble themselves.
The character can be changed into a debate focussed genuine Tytalus reasonably easily. Remove Diedne Magic, the Dark Secret and one of Twilight Prone or Rigid Magic, and replace with up to 3 points of flaws and an equivalent number of virtues. You are likely to also want to swap out their Prohibition and change the target of their Driven flaw.