In the inaugural issue of Ares Magazine, David Ritchie was not impressed by OneWorld, saying the game "takes the childhood game of 'rock breaks scissors' and attempts to dignify it by using that system (thinly disguised) to power a game." Ritchie concluded, "This one doesn't even qualify as cotton candy." He thought Annihilator held "a bit more interest", and despite the asymmetrical forces, "The result is a nicely balanced game which almost succeeds in overcoming the flimsiness of its premise." Overall, Ritchie gave the two games an extremely poor rating of only 2 out of 9.[1]
In the May-June 1980 edition of The Space Gamer (Issue No. 28), Denis Loubet was similarly unimpressed by either game. "OneWorld seems to take itself too seriously, and I don't know whether to believe the introduction or not. The counter mix is sort of unbalanced; the fog counters are of little worth, while the blades are the main attacking force." He had similar thoughts about Annihilator, calling it "just too small a game; there's not enough there. If there were more and different counters and a more complex and varied map, it might have the popularity of Ogre, but as it stands it's too small.".[2]
In the August 1980 edition of Dragon (Issue 40), Glenn Williams confessed that he bought Annihilator & OneWorld simply for Annihilator. However, he was very disappointed in the game, finding a number of issues with the scale of the game, its balance, and its weapons. He concluded that although "both the rationale and the mechanics of the game were poorly developed", the game could be adapted for other uses, and was therefore "worth the price." He concluded "Play the game a few times to learn it, then start making your own versions."[3]
In the October 1980 issue of Fantastic, game designer Greg Costikyan called Annihilator "simplistic and uninteresting; a 'publisher's note' says it is designed mostly for the novice player, but I don't think Metagaming should have bothered." Of OneWorld, Costikyan wrote that the game "has received mostly negative reviews; true, it is only mildly interesting to play, but its system and premise are more than a little amusing." Costikyan concluded, "Amusing — but not worth $2.95. What’s gotten into Metagaming, anyway?"[4]
In Issue 35 of Warning Order, Matt Irsik was ambivalent about Annihilator, saying, "The map, counters, and theme were a bit bland, but the game is playable." He was more impressed with OneWorld: "A fascinating fantasy game with a rock, paper, scissors type of combat system! The back story and topic were interesting to say the least."[5]
