If you fail to do this, your strategy simply won't work
Discard effects are predominantly black cards and most often sorceries (or abilities that can only be activated at sorcery speed) so that you cant make your opponents discard cards in their draw step
Another choice is to shut them down with cards like Stony Silence and Collector Ouphe that prevent artifacts from activating abilities
Anzrag, the Quake-Mole Ares, God of War Bhaal, Lord of Murder Birgi, God of Storytelling Djeru and Hazoret Havi, the All-Father Hazoret the Fervent Hazoret, Godseeker Ilharg, the Raze-Boar Iroas, God of Victory Keranos, God of Storms Klothys, God of Destiny Lady Loki, Agent of Chaos Loki Laufeyson Loki, God of Lies Loki, the Deceiver Mogis, God of Slaughter Ojer Axonil, Deepest Might Purphoros, Bronze-Blooded Purphoros, God of the Forge Purphoros, God of the Forge Sif's Spearmaster Surtr, Fiery Jtun The Locust God The Scorpion God Thor Odinson Thor, Asgard's Avenger Thor, God of Thunder Thor, Guardian of Midgard Tiamat Tom Bombadil Toralf, God of Fury Xenagos, God of Revels
Some listings are overpriced, but you have the potential to find a bargain from someone looking for a quick sale
In order to reflect this shift in Magic, Decorated Knight was the holiday card