The GM may let heroes push active abilities past their usual limits by paying FP – much as they would use extra effort to run faster, lift more, etc. (see Extra Effort, p. B356). It’s up to the GM whether to permit extra effort for all advantages, only for exotic or supernatural ones, or only for abilities that belong to powers.
In all cases, if an advantage offers specific rules for extra effort, use those rules instead. For instance, Clairsentience lets the user pay 2 FP per minute to double his range without a Will roll, and Warp lets the user trade more than 4 FP for a bonus to his activation roll.

Trading Fatigue for Effect
Extra effort can increase the raw “output” of any active ability with a quantifiable effect beyond its success roll. Examples include:

•Damage, for Innate Attack.
•Level, for Affliction, Control, Create, Leech, Obscure, Temperature Control, etc.
•ST, for Binding or Telekinesis (ST bonus, for Lifting ST or Striking ST).
•Top speed, for movement abilities (Flight, Tunneling, etc.), after multiplying for any Enhanced Move.

The GM may permit extra effort for certain passive abilities, too; e.g., DR with Force Field (extra effort increases DR) and attacks with Aura (extra effort works as usual for Affliction, Innate Attack, etc.). He might also allow it to enhance passive abilities for a Power Block (p. 168). In a high-powered supers game, he could even let it temporarily boost the points in a Modular Abilities slot.
To use extra effort, make a Will roll at -1 per 5% increase in effect or fraction thereof; e.g., Affliction 9 represents 12.5% more effect than Affliction 8, so it would require a roll at -3. The maximum bonus to effect is 100%, at -20 to Will.

Modifiers: +5 in the situations described under Emergencies Only (p. 102), regardless of whether the ability has that limitation. Unlike ordinary extra effort, there’s no penalty for missing FP – in heroic genres, heroes who are in danger and nearly spent seem more able to succeed at extra effort! If using a power, add a bonus equal to your Talent.

Succeed or fail, extra effort costs FP. Instantaneous feats (e.g., attacks) cost a flat 1 FP per use. For maintainable abilities (Flight, Telekinesis, Temperature Control, etc.), make the above roll once per minute of ongoing use, and pay 1 FP per roll. Should it matter, you must spend these FP after the Will roll and before the roll to use the ability.

Success means you gain the desired increase in effect. This doesn’t guarantee success at using your ability; you could still fail your Innate Attack roll and miss with your extrapowerful Bolts o’ Doom. On a critical success, you don’t have to pay FP for your extra effort.

Failure means you achieve only what you would have accomplished without extra effort. On a critical failure, you push your ability too far. It flickers off for a second – your attack is a dud, your force field provides no DR, your Flight cuts out in midair, etc. – and the task you were attempting fails. You must also check for crippling, as explained under Crippled Abilities (p. 156). This roll is for your entire power if your ability is part of a power. Failure indicates temporary crippling; critical failure means lasting crippling.

Trading fatigue for effect is impossible for passive abilities other than those described above, even for active uses; abilities that already tie effect to FP spent, such as Healing; and abilities with unquantifiable effects, such as Channeling.

Machines and Extra Effect: Those with the Machine meta-trait (p. B263) can’t use extra effort, but the GM might make an exception in campaigns with superscience mecha or space-opera starships. Start with the rules above, replace the Will roll with a HT roll, and mark off FP costs against HT. For machines with operators, the GM may replace the Will roll with a skill roll (against Engineer, Piloting, etc.), basing skill on the machine’s HT instead of the operator’s DX or IQ (see Using Skills With Other Attributes, p. B172). Handle HT losses, and repairs made to reverse them, as if they were due to missed maintenance (see Maintenance, p. B485).

Godlike Extra Effort: In campaigns intended to emulate heroic epics and over-the-top comics, the GM may let heroes trade more than 1 FP for extra effect. Use the same rules, but multiply bonus effect by the FP spent and ignore the 100% limit on the bonus. For instance, a hero who makes a Will-3 roll could burn 1 FP for 15% more effect . . . or 10 FP for 150% more effect. This greatly magnifies the power of heroes with large Energy Reserves (p. 119). Handle with care!

Trading Fatigue for Skill
You can instead put extra effort into focus and concentration to gain a one-time bonus to your success roll. This costs a flat 1 FP per +1 to the roll, to a maximum of +4. Since this use of extra effort actually increases control, it carries no risk of catastrophic failure. It’s up to the GM whether you can combine this with trading fatigue for effect.
This option is available for any active ability that requires a roll to activate or a Quick Contest with the subject. Passive abilities can’t use it. Neither can abilities that require an attack roll instead of an activation roll – the equivalent option for attacks is All-Out Attack (Determined).