What was stated by Rapidfire summarizes it very well. Here are some links to similar questions I answered in previous jams:
/jam/metroidvania-month-6/topic/605675/freebought-assets
/jam/metroidvania-month-7/topic/677025/when-should-we-start-worki...
/jam/metroidvania-month-8/topic/797754/quick-rules-question
/jam/metroidvania-month-8/topic/794612/expanding-upon-a-previous-...