Does Federal Rules of Civil Procedure Rule 12 permit a defendant to file successive, pre-answer Rule 12(b)(6) motion(s) to dismiss—each towards a separate claim—six months apart?

QUESTIONS PRESENTED * Does Federal Rules of Civil Procedure Rule 12 permit a defendant to file successive, pre-answer Rule 12(b)(6) motion(s) to dismiss—each towards a separate claim—six months apart? * Where as here, if a prisoner is subject to constant intra-facility transfers over a period of 24 months, does this constitute 'an expected parameter of the sentenced imposed by the trial court’? * Is it fundamentally unfair for the District Court to allow Petitioner's well documented claims of custodial abuse to remain in the pleadings stage, for 35 months before eventually dismissing the case? * Considering the nature and volume of the evidence lodged into the record, should the public-official defendants named below, be able to avoid liability for their overt acts/omissions? * After the United States Magistrate Judge declared that Petitioner stated a claim, did the ‘burden shift' ; within the meaning of Mt. Healthy v. Doyle, for the purposes of § 1983 retaliation claims? Where is the constitutional line drawn between pleading standards and burden of proof?