This could probably be done better with a table of streaks, text format strings, and sound references.

```lua
local Streaks = {
    [ 3 ] = {
        Text = "%s is on a triple kill!",
        Sound = Plugin.Sounds.TripleKill
    }
    --and so on
}

function Plugin:CheckForMultiKills( Name, Streak )
    local StreakData = Streaks[ Streak ]

    if not StreakData then return end
    
    Shine:NotifyColour( nil, 255, 0, 0, StringFormat( StreakData,Text, Name ) )

    self:PlaySound( StreakData.Sound )
end
```