Spelling both of them out and then explaining the sound seems strange to me here. Perhaps write out his full name spelled normally, then explain that it is all drunkenly slurred. Otherwise it is a little redundant and confusing, especially since they don’t match- why would you spell is ICK-RUS if it sounded more like ICKA-RUS?

Great alliteration here. "The Plasticine Clatter" sounds like an epic space event in Doctor Who. Or, an indy rock band. :)

I like the break in the tension that reminds you this is not an epic battle- just some kid playing with old toys. It’s very human element.