You can obtain the Joltik (1-Diamond rarity) card by opening Mew from Mythical Island set
Choose from a variety of options, including folded greeting cards, photo cards, and stationery cards
Each deck is based on a faction from the Warhammer 40,000 universe and boasts an impressive number of original cards for you to theorycraft
When there is a golden ring around the number, it means this card is eligible to be placed into your Inkwell as Ink
Indomitable Creativity (red), Jund (black/red/green), Death's Shadow (black/red/blue), Rakdos Midrange (black/red), and more decks make use of this discard spell to absolutely hose opponents playing burn or other hyper aggressive strategies
I've got a few extra bits and pieces to deal with organization, bulk, and color coding in my setup as well (more on that below), but if you're starting out as cheap as you can, you only really need the first two items on this list