One card for example has Leafeon rolling hay bales on a farm while another has Glaceon making an ice rink for other Pokmon
Currently, the MTG Arena economy lets you obtain cards in four different ways on Arena: crafting cards directly from wildcards, opening booster packs, drafting in non-Phantom events, and as random individual card rewards (ICRs) from daily wins and events like Midweek Magic
Theyll always be shown wearing the Stellar Crown (which is also the name of the set they debuted in), for example, and they have a sort of rainbow coloured border that makes them immediately visually distinct from other Tera Pokmon ex cards (though this latter point is not the case on the Hyper Rare, gold variant of the Terapagos ex card, as you can see below)
Yet, if you'd like to see it first, you can always flip the booster pack around before opening it
Now, however, there'll be a new option where you can permanently destroy the duplicate card for Trade Tokens