If you cast a spell using Malcolm, Alluring Scoundrel's last ability, you do so as part of the resolution of the ability
Because of the prowess triggers in the deck, sandbagging Gitaxian Probes until multiple Monastery Swiftspears and/or Stormchaser Mages are on the battlefield is a regular angle of attack
Both of these decks have some good cards, but also some bad ones
When any source deals damage to you or a permanent you control, they will lose two life unless they can pay one generic mana
The other 14.1%, you get a chance at the truly rare drops, the Japan Showcase versions, the Double Exposure and the Special Guests
Your other options for sacrificing Jumbo Cactuar, however, might be even more interesting than Ruthless Technomancer