This could be a metaphor for reflecting the bond and common ground between you, though showing that connection through emotions is probably a better idea
The main culprit is the huge power creep that MTGs had across the last few years, printing cards especially creatures that are more powerful than old Snappy in a vacuum
If you need to catch up, you can read the previous article, about the Sealed Deck format, or start at the beginning with The Basics
I dont currently have a +1/+1 counter-themed deck that this would nicely fit into
Closely related sets that share a prefix, or set with multiple subsets within them (such as Yugi's Legendary Decks), will often replace the first character of the set position number with a letter (different for each set or subset), and number each set or subset separately
With up to 99 Dalmatian Puppies in your deck, thats a lot of ink