Flaws
A flaw can be something you're vulnerable to, weak against, or restrictions on your powers. They are essentially negative ranks in powers and specialties, granting you bonus XP in exchange.
BANES
Banes are essentially the same as boons but are negative detriments instead of helpful blessings or items.
RESTRICTIONS
Restrictions are specific drawbacks or conditions you suffer or need to use your power. For example, having the Sea power but only being able to use it when a lot of water is present would be a minor restriction. Only being able to use it while underwater in the ocean would be a major restriction.
WEAKNESS
Weaknesses that function as negative power or specialty ranks. You gain XP instead of spending it for every rank in such things. Unlike powers and specialties, your flaw always applies any time anything falls within its purview and penalizes your power and specialty ranks when resisting anything. For example, if you had a flaw called Slow (negative rank with Alacrity) and any attack targeted you which Alacrity could feasibly be used to resist, you'd apply your Slow rank as a penalty to whatever power you use to defend against it. A negative defense rank means you give the attacker bonus dice to their attack.
VULNERABILITIES
A vulnerability is that normally doesn't hurt an adult human at all but does hurt you. Any time you're exposed to your vulnerability, it damages you automatically, rolling your vulnerability rank and adding the successes to the damage created.
GM LIMITS
Your GM may limit how much XP you can acquire from weaknesses, typically the limit is equal to half your starting XP during character creation. Thus, you could start with up to 50% more than the normal starting XP by creating weaknesses and restrictions on your abilities. Talk to your GM about unique restrictions and weaknesses you come up with.