Marie Primer+Build Outline

Spell Primer:

Whenever Marie casts a spell, there's a 10% chance that she'll trigger a wild magic effect. So if the d100 is 10 or less, roll again and use the result of that to look up the wild magic table for whatever sphere she's using. For example, if she's casting a cure spell of the life sphere, and she rolls a 7 on the first d100, then she'd roll again for say a 42 and reference the wild magic table at the bottom of the life sphere's page on the wiki.

Now for the confusing part. Flexing talents. Basically, the whole idea of Marie's build is that she can cast spells that she doesn't normally know by temporarily gaining knowledge of certain spheres and talents. She can do this in a number of ways. The all-day access method is to shape one of the sphereshaper's veils, which grant access to a sphere. Most days she'll have Alterator's Touch (https://libraryofmetzofitz.fandom.com/wiki/Alterator%27s_Touch), for example, to improve her mundane weaving abilities. But she can alternatively shape any veil from either of these two lists:
http://spheresofpower.wikidot.com/sphereshaper-veils
https://libraryofmetzofitz.fandom.com/wiki/Sphereshaper_Veil_List
And when she does, she can select an additional bonus talent from that sphere. So for example, she could shape Shaded Spirit (https://libraryofmetzofitz.fandom.com/wiki/Shaded_Spirit) to gain access to the dark sphere and then take a talent like Shadowed Mien. You can ignore the bind effect for these veils, and whenever it discusses essence, you can assume she has 1 invested. These benefits last all day, so it's good to pick up a sphere/talent this way that she'll need to use continuously throughout the day.

The default, round-by-round method of flexing is for her to do an Inspired Surge, where she basically accepts +100% wild magic chance for access to a talent from a sphere she already knows. This is the most limited flexing ability she has, but she can use it at will, so it's a great way to shore up some abilities (like getting access to advanced Life sphere talents to remove bad wild magic results). The +100% wild magic chance means that she's guaranteed to roll on the wild magic table for whatever spell she's casting, and there's a 10% chance that she'll have to roll on the major table instead:

http://spheresofpower.wikidot.com/wild-magic#toc29

Additionally, she has 1 shadow point that she can spend to give herself access to new talents or spheres. This can be used in conjunction with any of the flexes above, but she only has the 1 point per day and it costs a point each time she does so (though she can trade spell points for more shadow points). This gives her access to Alteration, Conjuration, Creation, Dark, Death, Destruction, Enhancement, Light, Nature, Protection or Weather sphere for 1 minute (or until she spends another shadow point). Note that until she gets Emulation Expert next level, these effects only count as illusion sphere effects, so talents gained through shadow flexing can't serve as prerequisites for other flexes (yet).

Finally, Marie can use her Adaptation class feature to flex into a talent as a standard action. This is her second most limited form of flexing, as she can only do it 4 times per day and she must flex into a talent from a sphere she already knows. Otherwise, it's not a bad method to flex, particularly if time is not an issue, so she usually reserves this for out-of-combat puzzle-solving. Another upside of this is that she can flex into metamagic feats, so it might help her get out of some tight spots.

Ideally, this means that she can reach four talents deep into most spheres, but, in practice, she'll only be able to flex one or two talents deep into any given sphere. That's enough to pull off things like that Death sphere Control Undead talent, but not most advanced talents, for example.

Generally, she's a 1st level caster with DC 15 spells and 7 Spell Points. Not all spells require spell points, but when in doubt, assume they cost 1 SP. She gets a +2 CL for Illusion spells and that increases their DC to 16. MSB is +2, MSD is 13, and Concentration is +7.

Sequencing:

The other tricky part of Marie's build is her sequencing abilities. As a Chromamancer Prodigy, Marie can assemble little step-by-step combat-only combos called sequences. These include an opening paired with an imbue, up to 4 links, and a finisher. For each sequence, she basically chooses a sphere and a color. The openers, imbues, links, and finishers must be chosen from either those available to that sphere or that color. She can't change the color once she's started a sequence (without terminating it), but she can change the associated sphere as a swift action. Typically it's best to pair offensive spheres (like destruction) with defensive colors (like blue) or vice versa with defensive spheres (like protection) with offensive colors (like red). This gives her the option of choosing either an offensive or defensive finisher, depending on the needs of the moment. She does need to have access to the sphere to use it in a sequence. She always has access to all the colors, however.

Most parts of a sequence can be combined with other actions, and the finishers are usually the payoff for jumping through all the previous hoops. Generally, sequences are stronger the more links she maintains, so Marie's most powerful effects usually come into play after a few rounds of combat. When she chooses an opening, she also chooses an imbue, which usually grants an ongoing bonus for the length of the sequence.

One of Marie's most powerful abilities is the Fast Magics link, which allows her to cast a sphere spell as a move action. She can't cast two spells from the same sphere in the same turn, but otherwise she's free to mix things up, so this is a good way to build her sequences while making the most of her action economy.