Amazon: While not as specialised as other platforms, Amazon often has a wide variety of MTG products, including booster boxes, decks, and accessories
To support it without relying on it, I prioritized artifact mana acceleration like Thran Dynamo, Basalt Monolith, and all the artifact creatures I could get
As an added extra, you'll also be able to exile foretell cards in your opponent's turns as well, keeping your mana open for as long as you need it
Watery Grave just reminds me of what happened to my weed when I was home from college for the summer and my parents started walking up to my bathroom. Sadly, the card is too expensive to be used as toilet paper (Honorable mention: Scapeshift, Shadow of Doubt, Restoration Angel) $10-$15: Aven Mindcensor I like to play W/b Martyr in Modern, and its bad matchups these days are mainly decks that do degenerate stuff like searching their library for a whatever-card combo (MPod, KPod, RG Tron, Titan Scapeshift), so I proudly packed three Aven Mindcensors in my sideboard and thought that nothing bad could happen again
Burn spells are essentially a way of life in Magic