The Knight of Weeks 
Legendary Creature — Human Knight
Lifelink, vigilance, first strike At the beginning of your combat step and whenever another Knight enters the battlefield under your control, put a day counter on The Knight of Weeks. The Knight of Weeks gets +7/+7 for every seven day counters on it.
Legality
standardNOT LEGALpioneerNOT LEGALmodernNOT LEGALlegacyNOT LEGALvintageNOT LEGALcommanderNOT LEGAL