Activate Chivalric Alliance by paying 2 and discarding a card, creating a 2/2 Knight creature token.
When the Knight enters the battlefield, Marneus triggers, causing you to draw a card.
Activate Ashnod's Altar by sacrificing the Knight, adding CC.
Repeat.
This loop is a masterclass in recycling resources, transforming mana and discarded cards into a seemingly endless stream of value. By paying into Chivalric Alliance's ability, you produce a Knight token that immediately triggers Marneus Calgar's Master Tactician ability, replacing itself in your hand by drawing a card. You then feed that same token directly to Ashnod's Altar to generate the colorless mana needed to fuel the next cycle, letting you dig endlessly through your deck while constantly feeding your graveyard.