Challenge: The Penny Card Cap

The idea: pick an agreed pricing reference (a specific retailer, or a site like Scryfall/TCGplayer for a market-price snapshot) and a small per-card ceiling — say £1. Every nonland card in the deck except the commander must individually price under that cap at the time you build. The commander itself can be anything, since that's the one card everyone's building around.

Why it stays interesting

This is a different shape of budget challenge to a total-deck cap: instead of one expensive bomb and a pile of filler, you're forced to find 60-70 genuinely cheap cards that work well together — which tends to reward synergy and card selection over raw power.

Cost control

This directly targets the exact problem in the brief: a single, uncapped expensive card can't win the deck for you, because every card has the same low individual ceiling. Pair it with the Single-Store Budget Cap challenge if you also want a hard total, though in practice a strict per-card cap on ~70 cards rarely needs one.