Växjö started by getting a penalty which scoring machine Kalle Kossila took care of.
But he lifted the shot just above the goalkeeper's left cross.
Instead, it was Oskarshamn who were able to take the lead in the second period and then pull away.
Jiri Smejkal made it 1-0 and a few minutes later IKO scored two goals in the space of a minute and a half to make it 3-0.
Smejkal was not finished.
In a numerical disadvantage, 4-0 came from the Czech.
His eighth goal in the last five games.
With that, Smejkal is now in third place in the SHL's scoring (36 points) with his teammates Patrik Karlkvist and Antti Suomela in front of him (45 and 47 points).
The goals kept coming for Oskarshamn.
Karlkvist played until Max Powell's 5-0 and Suomela made it 6-1 shortly after Växjö reduced.
The match is in progress, it says 6-1.