mtg cards that discourage attacking prevent Impulsive Maneuvers [Odyssey] Discourage the discard!

If youre interested in experimenting, a more achievable challenge might be the Guildpact Challenge: brewing a deck for each of the 10 Ravnica Guild Pairs

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Finding out which cards are the most valuable also tells you which cards are most important, and discovering what makes those cards worth their asking price is an easy way to understand which concepts are powerful and universal to the game of Magic

It's an optional additional cost which you can pay or not as you cast the card

You can slam it down pre-combat and connect with what you already have in play