The Mauler mutagen ability reads:
Mutagen (Su)
At 1st level, a mutagenic mauler discovers how to create a mutagen that she can imbibe in order to heighten her physical prowess, though at the cost of her personality. This functions as an alchemist’s mutagen and uses the brawler’s class level as her alchemist level for this ability (alchemist levels stack with brawler levels for determining the effect of this ability). A mutagenic mauler counts as an alchemist for the purpose of imbibing a mutagen prepared by someone else.
At 6th level, a mutagenic mauler gains a +2 bonus on damage rolls when she attacks in melee while in her mutagenic form. This bonus increases to +3 at 11th level, and to +4 at 16th level. At 10th level, a mutagenic mauler learns one of the following alchemist discoveries: feral mutagen or infuse mutagen, preserve organs, spontaneous healing. At 12th level, the mutagenic mauler learns the greater mutagen discovery.
This ability replaces martial flexibility.
And the extra discovery feat reads as:
You have made a new alchemical discovery.
Prerequisite: Discovery class feature.
Benefit: You gain one additional discovery. You must meet all of the prerequisites for this discovery.
Special: You can gain Extra Discovery multiple times.
My question is once the MM hits level 10 and learns the first discovery is it able to take the feat to gain one of the other ones it qualifies for?
No. Despite getting access to a select few Discoveries, you lack the actual Discover class feature to qualify for Extra Discovery.
I agree with VoodistMonk on the rules as written.
However, I'd allow you to take the feat at my table, but only to pick from the discoveries that were listed as available to you: feral mutagen, infuse mutagen, preserve organs, and spontaneous healing.
I agree with VoodistMonk on the rules as written.
However, I'd allow you to take the feat at my table, but only to pick from the discoveries that were listed as available to you: feral mutagen, infuse mutagen, preserve organs, and spontaneous healing.
That is also how I would rule it at my table too