GUTTERBALL

MAGNACARTADocument sealed at Runnymede in 1215 (5,5) CEREBRATEDThought before entering bet, card getting dealt (10) ZZZZFUYWUYBear of children's rhyme MINDTHEGAPWarning on exiting tube train (4,3,3) STRIPPOKERCard game that's really taking off? MEMORYLANETake a nostalgic trip down this (6,4) THATDOESIT"Enough already!" ZZBUALDRINAstronaut for whom a Pixar character is named METHUSELAHBiblical patriarch – bottle holding six litres of wine (10) BIGBROTHERUbiquitous leader is great alongside fellow union member (3,7) HIGHSTAKESWith a lot on the line, or a phonetic hint to 3-, 8-, 15-, and 23-Down SUPERWOMANShe flies American back every week to country (10) AUTHORSHIPWriting this, hour wasted filling a puzzle at the beginning (10) ALASKAROLLSushi bite topped with salmon