Theres a lot of established heuristics on this subject, and a few points I can toss in to help you construct an optimal mana base for Standard, Modern, Pioneer, or whatever MTG format you prefer
Sample Upheaval Deck | Odyssey Constructed | Abe Sargent Creatures (4) 4 Psychatog Instants (18) 2 Memory Lapse 2 Recoil 2 Repulse 4 Aether Burst 4 Counterspell 4 Fact or Fiction Sorceries (14) 3 Chainer's Edict 3 Deep Analysis 4 Duress 4 Upheaval Lands (24) 10 Island 10 Swamp 4 Salt Marsh This is a common control deck that uses Upheaval to delay the game and then drops the Psychatog to win
Another strategy against Mew ex is feeding it a tanky card with minimum damage
Here is the list of newly banned MTG cards, as of December 2024: Jegantha, the Wellspring is the card banned in more than one format
The reason I'm writing this article now is that the latest set released the other day, "Twilight of Lorwyn," has been added to Jump In
This deck contains: 1 60-card starter deck including 2 foil cards 11 Tokens 1 Rulebook 1 Rise of the Floodborn Booster pack containing 12 randomized cards Decklist: Amethyst & Steel 2 Beast - Forbidding Recluse 2 Benja - Guardian of the Dragon Gem 3 Chip the Teacup - Gentle Soul 2 Cinderella - Knight in Training 2 Dr