KRO ragnarok(0618) and KRO ragnarok renewal(0618)
Or follow the instruction from which ever the server you are playing suggest you to download. Some servers might be using the older client and only work with sakray. So it's hard to say. I think if you got ragnarok without sakray you can still rename the data.grf into sdata.grf to play a sakray supported server (do remember to rename it back to original when trying to patch).
