Anyone heard of or played such a convention? Opening 2♣ with two alternatives, a. balanced hand with 17-18 points (could also be 18-19 or 19-20, whatever fits best into your system) b. weak 5-5 two-suiter, major+other It seems to work, the responses are pass = weak, (4)5+♣ 2♦ = all hands that does not fit into other bids. Opener bids cheaper major with a 5-5 and 2NT with a balanced hand. Opener may user higher bids to show 6-5 or better, 2♦ usually includes some strength (about 7-14) 2♥/♠ = to play, against both handtypes 2NT = asking, GF, normal Wilkosz responses (3NT free for balanced alternative) 3♣ = invitational three-suiter, short spades higher = as in Wilkosz, not sure if one should use 4-level bids. 2♣-2♦-2♥-? 2♠ = pass or correct higher = natural, should probably be invitationally oriented. Could probably develop some paradox-like stuff. 2♣-2♦-2[NT]-? 3♣ = Stayman 3♦ = to play, all other rebids are natural GF It has a lot common with standard multi, so maybe multi-Wilkosz could be allowed where multi is allowed? It could be used even in a natural system, all you need is to use 2♦ as strong.