Dne Utrotare:
Is there a limit to how many fatigue points mages/elementalists can buy?
The standard limit in Dungeon Fantasy is 1.3xHT. So with a HT of 12 your FP maximum would be 18. Casters are meant to buy Energy Reserve* at 3/lvl (maximum 20) to have more 'casting endurance'.
However, as Barbarians can exceed their maximum HP with a Barbarian specific Perk (Mountain of Meat, let's them go to 2xST), the GM might allow something similar to casters (like a Perk, call it say Second Wind, which might let them go to 1.5xHT).
Energy Reserve has its advantages and drawbacks compared to FP. Advantages: It recovers indepently of what you are doing at a rate of 1 per ten minutes, and is boosted by 'supernatural' FP recovery methods (Recover Energy spell specifically). Drawback: It can't be spent to avoid losing Fp to attacks or mundane FP expenditures, it's just for spells and supernatural abilities granted by your 'class'.
* Scholars and non-casters have a different maximum. Scholars have no maximum, but their ER can only be used for their very specific abilities, and everyone else can buy up to 3 levels for using Scrolls, Wands, etc.