- 50% chance: 1st cast successful and W mana spent
- 25% chance: 2nd cast successful and WW mana spent
- 12.5% chance: 3rd cast successful and WWW mana spent
- 6.25% chance: 4th cast successful and WWWW mana spent
Overall, this averages out to close to 2 mana spent on average to successfully copy and cast a spell. This is quite a good rate, and something that works very well with 0-1 mana spells, as the variance is less impactful. With Krark's Thumb it even goes down to just over 1.3 mana average to cast and copy a spell. To make the best use of Krark's ability, the list contains 3 free instant spells and 16 1 cmc instant/sorcery spells. The list also has various effects that trigger off of casting spells (Guttersnipe, Young Pyromancer, Monastery Mentor, Firebrand Archer, Blind Obedience) or don't care about being returned to hand (Shattering Spree, free spells).
For a partner, Tymna the Weaver seemed like the best option, as she provides two additional colors and a lot of draw power. Some further creature support for Tymna, various disruption pieces and recursion to help Tymna and Krark stay on the field, round out the list.
This deck plays out a lot like an EDH version of Mardu Pyromancer, with cheap spells, disruption, plentiful card advantage and difficult to deal with threats.
Happy to hear your thoughts and what cards could be good additions.
Decklist
Instants (sorted by cmc)
26 Mogg Salvage
28 Dark Ritual
32 Pyroblast
35 Tithe
36 Boros Charm
37 Brought Back
39 Rakdos Charm
Planeswalkers
Lands
70 Marsh Flats
75 Arid Mesa
80 Badlands
81 Plateau
82 Scrubland
83 Blood Crypt
87 Luxury Suite
88 Savai Triome
90 Wasteland
91 Strip Mine
92 Swamp
93 Swamp
94 Swamp
95 Plains
96 Plains
97 Plains
98 Mountain
Approximate Total Cost: