Death's Fervor

Upon casting this spell, the caster's body floods with a magical stimulant that heightens their physical abilities at the cost of their magical aptitude. For the duration of the spell or until concentration is dropped, the caster's STR and DEX are treated as 18 unless they are higher, their movement speed is doubled, they gain 15 temporary HP, and their weapon attacks are considered magical for the purposes of overcoming resistances. They are also proficient with all weapons for the duration and gain a +2 to AC. However, once the spell ends, the caster suffers from the withdrawal of the surging magic empowering their body. The caster cannot cast levelled spells for as many rounds as they maintained concentration on the spell, and they cannot use magical abilities during the spell's effect. Their movement speed is also reduced by 10 feet. Also, the caster must roll a d20 when the spell has ended, on a 1 they gain a point of exhaustion that can be removed with a short rest. If this spell is cast more than once per day, there is a scaling chance that the caster's magical abilities are inhibited for a longer period of time. On a second subsequent cast the caster rolls a d20 when the spells ends. On a 5 or lower their magical abilities are disrupted for the next 24 hours. The DC scales by 5 for each subsequent cast (DC 10 for 3rd cast, DC 15 for 4th cast, DC 20 for 5th cast). When casting a spell, the caster must roll a d20 and add their spellcasting ability modifier to the total. The DC for the roll is 12 + spell level. If the caster fails the DC, the spell fails, though they do not lose the spell slot.