Up to Nosferatu

𝐒𝐮𝐝𝐨𝐤𝐮

• Each row, column, and 2x4 region has to contain the digits from 1 to 8 once each.

𝐍𝐨𝐬𝐟𝐞𝐫𝐚𝐭𝐮 𝐚𝐧𝐝 𝐏𝐫𝐞𝐲

• Place one Nosferatu and one Prey cell in each row, column, and 2x4 region such that each Nosferatu cell is orthogonally adjacent to exactly one Prey cell.
• Both Nosferatu and Prey cells have to form a complete set of the digits 1 to 8, i.e. no two Nosferatu cells may contain identical digits and the same holds true for the Prey cells.
• The value of a cell that is not Nosferatu or Prey is its digit. The value of a Nosferatu cell is the sum of its digit and the digit in the adjacent Prey cell. The value of a Prey cell is 0.

𝐔𝐩 𝐭𝐨 𝐍-𝐬𝐮𝐦𝐬

• A clue outside the Row or Column N indicates the sum of all values up to the first cell seen from the clue that contains the value N. (The value N itself is not included in the sum.)