[1] EDH - Competitive: Power lvl 9-10
10: Tier-1 cEDH
The most powerful decks in the format. Every card is hyper-efficient, and consistency is almost on a card-for-card basis. Power play and instant-speed interaction are thrown around like waterballoons. While inexpensive decks can be here, budgetless version of them are almost always going to reign supreme due to efficiency.
9: Tier-2 cEDH
Decks have no "fat": every card matters; every play is impactful. Decks have several specific lines of play. You're expected to make multiple plays a turn from turn 1, if not sooner; you must be ready to interact just as quickly. Boardstates are less important that in lower levels. Bugetless decks are common, but some decks aren't very expensive.