•Facts: MARCO openly admitting that his healing is fundamental for him to be able to deal with the KING and the Queen, who are not giving their all, if you notice, it was only 1x1 between MARCO and KING, with MARCO sneaking and attacking the QUEEN unprepared, which means that ALL of that time was only 1x1 between MARCO and KING, while KING has exhausted all physical capacity and is probably about to exhaust the regenerative, causing incurable damage to MARCOS ,which is comparable to GARP's punch in MF, which caused incurable damage to MARCO.
•King is the real beast of SPOILERS, while MARCO faces KING at his best, yes, this is MARCO's best form of combat, he used it against aokiji, akainu, kizaru, BIG MOM, this is his hybrid, any other assumption will be just a mere guess.