Sure, it's not a wise financial decision, but when it comes down to it, Magic is a game we play for fun, and if "fun" to you means jamming a bunch of Squirrel Tribal in unranked games, you should 100% do it
69 Common cards
This is not just me, on EDHREC.com, the Arena is in 240,548 decks and Sign in Blood in 179,435, so tens of thousands less
it kind of makes the bottom of the card look bulbous
If the creature you control already has a Role that you control attached to it, that Role will be put into its owner's graveyard as a state-based action after the Monster Role is attached to it but before the reflexive triggered ability resolves
Some people start with index cards and markers a fine place to begin