"If you can do one thing, hone it to perfection. Hone it to the utmost limit." - Jigoro

Prerequisites: First level only

Benefit:

Whenever you gain access to a new spell level, you choose one spell that you know. This spell is now the only spell you can cast and its DC increases by one. However, you can still use cantrips and spell-like abilities.

All your spell slots from spell levels other than cantrips are transformed into slots of your chosen spell relative to their value. To calculate your spell slots, add up the number of spell slots from each level and multiply them by their respective spell levels, then divide by the level of your chosen spell. For example a 5th level magician with 17 intelligence would have 7 1st level spells, 6 2nd level spells and 4 3rd level spells (including bonus spells from attributes). If he chooses a 3rd level spell, he now has (7*1 + 6*2 + 4*3) / 3 = 10 3rd level spell slots.

Since the focus of your studies is so narrow, you can learn the Arcane Master Thesis Feat even if you only have the Arcane Thesis Feat for your chosen spell istead of three times.