Rakdos Reanimator is the same fundamental threat as UBG Reanimator — a turn-one combo deck using Dark Ritual, Lotus Petal, and discard outlets to reanimate Griselbrand or Atraxa as fast as possible, except this build skews heavier on redundant reanimation spells over countermagic backup. Leyline of the Void is the cornerstone of your sideboard plan, placing it from your opening hand before they can execute the combo and exiling everything they discard or loot away for the rest of the game. Chalice of the Void on one hits Reanimate, while Chalice on zero stops Lotus Petal and reduces the explosive mana they need; combining Chalice with Leyline in the same opening hand is often an immediate concession from them. Thought-Knot Seer is valuable for stripping Animate Dead, Shallow Grave, or a reanimation target before you can land Leyline, bridging the gap in games where your enchantment doesn't appear in the opener. Their post-board Show and Tell plan is an additional angle — your large Eldrazi bodies like Thought-Knot Seer and Glaring Fleshraker can be put into play off Show and Tell to race their cheated threats.