If you would roll one or more dice, instead roll that many dice plus one and ignore the lowest roll. Whenever you roll one or more dice, put a +1/+1 counter on Wyll, Blade of Frontiers. Choose a Background (You can have a Background as a second commander.)

Whenever you roll one or more dice, put a number of charge counters on Vexing Puzzlebox equal to the result. {T}: Add one mana of any color. Roll a d20. {T}, Remove 100 charge counters from Vexing Puzzlebox: Search your library for an artifact card, put that card onto the battlefield, then shuffle.

Flash Cone of Cold — When Scion of Stygia enters the battlefield, choose target creature an opponent controls, then roll a d20. 1—9 | Tap that creature. 10—20 | Tap that creature. It doesn't untap during its controller's next untap step.

(Gain the next level as a sorcery to add its ability.) If you would roll one or more dice, instead roll that many dice plus one and ignore the lowest roll. {1}{R}: Level 2 Whenever you roll one or more dice, target creature you control gets +2/+0 and gains menace until end of turn. {2}{R}: Level 3 Creatures you control have haste.

Choose target spell or ability with one or more targets. Roll a d20 and add the greatest power among creatures you control. 1—14 | You may choose new targets for that spell or ability. 15+ | You may choose new targets for that spell or ability. Then copy it. You may choose new targets for the copy.

{T}: Add {C}. {5}, {T}, Exile Underdark Rift: Roll a d10. Put target artifact, creature, or planeswalker into its owner's library just beneath the top X cards of that library, where X is the result. Activate only as a sorcery.

Choose target creature an opponent controls, then roll a d20. 1—9 | Return it to its owner's hand. 10—19 | Its owner puts it on the top or bottom of their library. 20 | Gain control of it until the end of your next turn.