A Pokemon or a scene might play a role in giving a card a distinctly Halloween feel, but the combination of a creepy scene and a terrifying Pokemon is Halloween personified
Finally, I would head to EDHREC just to see the staples that are played in Grixis colors, as well as for your commander and whatever theme you choose to go with
However, if a card has been reprinted and appears in an eligible deck, any version of that card will be legal to play
This also created a bunch of awkward errata, as the card Rolling Stones which used to simpy say "Walls can now attack" now says "All walls lose defender"
For a Red spell, it is surprisingly distant, slow, and contemplative, using the panel shape to convey this relatively lasting sorcery
She gives you additional mana to help cast your expensive powerful angels early, and boosts their stats by adding +1/+1 counters to them