Upgrade is a card is a card depicting a yellow upwards-facing arrow.
This card was created by fivexthethird.
Upgrade has 1 heart and 0 attack. You can use it on a card to "upgrade it", doubling the card's hearts and attack. This destroys upgrade.
- As it has a heart, it can be assumed that upgrade can be played as a regular card instead of upgrading another card if you wish.