Mana Crypt (Kaladesh Inventions Series) The most valuable Magic card not on the Reserved List, Mana Crypt is valuable for similar reasons as Mana Vault and Sol Ring: it can easily add a lot of extra mana to the mana pool and enable some explosive early plays in a game
Heck, even the Trainer cards are getting a few 'awws' out of me
It can take quite a while to build up enough points to purchase the rarer cards in each set, so these are best saved until youre only missing a handful of cards for your perfect battling deck

Here are all of the budget instant speed green card draw spells you can include in your decks: Charge Through Target creature gains trample until end of turn Draw a card Hunters Insight Choose target creature you control Whenever that creature deals combat damage to a player or planeswalker this turn, draw that many cards Inspiring Call Draw a card for each creature you control with a +1/+1 counter on it Those creatures gain indestructible until end of turn Viridescent Wisps Target creature becomes green and gets +1/+0 until end of turn Draw a card Warriors Lesson Until end of turn, up to two target creatures you control each gain Whenever this creature deals combat damage to a player, draw a card Here is a pre-populated list of all of those 2 mana instant speed green card draw spells I was mentioning
Either way, it shuts down a lot of the biggest threats you'll face, from scary creatures to even scarier planeswalkers - and all for two mana
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