Probably gets to the Creeper before dying. Myers might kill him too.
There's really no getting around the fact that his "true form" was tipped as though it were a ****ing cow and then had its heart ripped out by middle age people.
The real problem lies in getting past Pennywise' mental powers. Of all the ones listed, only the last 4 have the power to surpass Pennywise in that category. The rest can fall to his mindf**kery and deadlights.
Ah, your reffering to plot there, and they needed to be all together for that to work. Individually they got messed up bad, with one even committing suicide at the thought of his return.