Because many Pokemon have multiple attack options, you must announce the attack before calculating damage dealt
Archmages Charm is extremely pushed, a solid permission spell, a good way to build card advantage for hitting land drops, and a fantastic tool against Deaths Shadow, Wild Nacatl, Goblin Guide, Pyxis of Pandemonium, Champion of the Parish, Aether Vial, Delver of Secrets, Hardened Scales, Amulet of Vigor, Benthic Biomancer, Glistener Elf, Noble Hierarch, Viscera Seer, and sometimes even Hexdrinker (just to mention a few)
If a single spell has multiple instances of Cascade, each triggers separately
Wilds of Eldraine launches on September 18
Pikachu ex can be obtained from Genetic Apex: Pikachu, Genetic Apex: Charizard, and Genetic Apex: Mewtwo packs in the Genetic Apex set
Tragic Trajectory is nice for sure, but sorcery speed really hurts