Grimjow stomps. A Gran Ray Cero would erase Tien from existance
I know right! Grimmeow can also use his neko koneko claw slash to slash out Tenshinhan's third eye. With his zanpakuto he can cut Tenshihan's extra arms. Tenshihan will be screwed if Grimmjow goes release.
Also, he can use his stomach hole to avoid Tien's ki blasts. They will go through the hole and Grimm will use that as an advantage to destroy cyclops man.