After the banished General Slade is found on earth, Clark realizes the Phantom Zone portal must be open and decides to go close it, however dangerous as his super powers don't work there. Oliver was denied coming along but managed by surprise. The heroes find the zone under the rule of General Zod, who looks forward to his revenge for both worlds on Clark and was promised full dominion by Darkseid if he eliminates the great Kryponian adversary. So Clark is forced to enter Zod's arena's mortal gladiator combat, while Oliver is offered an alternative and reminded of being Omega-branded already, which no earthling knows yet. In the Watch Tower, Lois discovers the three hours portal destruction 'safeguard' Clark ordered Tess to trigger and fights it.
Did You Know?
Near the end you see Clark rip off his shirt and buttons fly off when he does, this would be the first time in the entire history of Superman in all genres that buttons fly off his shirt when he rips it open to reveal his uniform underneath. See more
At least here, you're on equal footing with Kal-El. Having to work alongside with someone with the powers of a god must be so demoralizing.
My ego's firmly intact, thank you very much.
References The Wizard of Oz