How to upgrade a Commander precon mana base

Start by counting lands and identifying which spells you want to cast on turns one through four. Avoid cutting lands simply because you added a mana rock: rocks still need mana to cast, and can be removed. Check the land-drop calculator before reducing your starting count.

List lands that always enter tapped and which colors they provide. Prioritize replacements that support early spells and your commander. Keep a slower utility land when its effect is central to the deck, rather than replacing every tapped land indiscriminately.

Read the exact wording on your ramp spells before replacing basics. Some find only basics, others find Forest cards, and others accept more land types. Keep enough legal targets and review how your changes affect each spell.

Select your commander in Landfiller, set a budget, and inspect source coverage and tapped-land counts. Record lands you own before reviewing the shopping list. Your deck’s unusual costs or local playgroup may justify changing a recommendation.