Drop-Drop is a puzzle arcade game, probably inspired by Tetris and Columns. There is a rectangular playfield. Various blocks appear slowly from the top. If one of the columns would reach the bottom, the game is over. The player has a cursor at the bottom which can be used to select a particular column, pull blocks into that cursor the bottom, move the cursor to a different column and push the blocks back to the top. Multiple blocks can be moved at once, but they have to be the same type. As soon as the column of at least 5 blocks of the same type gathers together, this group annihilates, freeing up space on the playfield, thus making it possible to continue the game. Drop-Drop was initially developed and published in Russia; the only known names attached to the project are programmers Vladimir Ryshov and Grigory Sragovich. The game was included in the Moscow Nights game compilation, which released in (at the very least) the United Kingdom and Germany. Data East learned of Moscow Knights and obtained a license for Drop-Drop, using it as the basis of what would eventually be known as Magical Drop. Both the first Magical Drop and Magical Drop II state that the gameplay was licensed from Russ Ltd, and Japanese materials for the first Magical Drop and its ports play up the game's status as a Russian puzzle game. At some point, Data East would purchase the full rights to the game from Russ; this is likely the reason why Russ is not credited in Magical Drop III or beyond.