If you win, at the beginning of your next main phase, you may add X to your mana pool, where X is that spell's converted mana cost
All of the cards near the top of this list do both things, and should be your first includes in an MTG Rat Commander deck
Brawl Legal Vintage Legal Timeless Legal Commander Legal Pauper Legal Oathbreaker Legal Penny Not Legal This Secret Lair Drop was pulled/delayed and this version of the card may not exist in public
It can also be a Coastal Piracy for one turn with warp
While overall look and feel is quite comparable to Katana (with the noticeable difference being a bit of extra sleeve at the top of your cards), Dragon Shield retains its excellent shuffle feel a little longer than Katana does, so at the end of the day we prefer this well known card sleeve just a hair over Katana
More importantly, we actually did sweet things with Panharmonicon, generating tons of value and eventually using that value to win games