The spider was added in Beta 5.2. Previous Versions can be found here.
Possible use may be as a rush card in a Bravery deck. In Beta 9.1, it was the second card to receive Haste, the first one being Lemon Bread.
It's not recommended to place this by itself against Justice as it will be killed by its passive effect.
Spider can also be useful in an Arachnid based deck, being able to trigger the Synergy effect of Spider Bakery and Spider Flower while also being affected by Spider Sign. It's also the cheapest way to buff Muffet, giving +2/+1 for only 1G while still being able to attack a monster (and give room to summon new monsters when it dies in the process).
Card Skins[]
Little Pet
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