this is an old era plugin, dont expect it to work 100% like the new clanwar one that era uses now.
- sm_1v1 or !1v1
- sm_cancel1v1 or !cancel1v1 Only admins have acess to this command
Put the .smx file into your plugins folder (in your server files). -> csgoserver\csgo\addons\sourcemod\plugins
Pick 2 players, the number of rounds and if you want hp rule (wins the round the player which has more HP)