en_tn_condensed/ezk/21/22.md

In his right hand will be an omen about Jerusalem

This means the he will hold one of the articles of his divination that was read as an omen against Jerusalem in his right hand. Alternate translation: "In his right hand will be an article of divination with an omen against Jerusalem" (See: rc://en/ta/man/translate/figs-metonymy)

battering rams

A battering ram was a cut tree or large log with a sharpened end or an end covered in metal. It was held by several men who would pound the end against a wall.

to build a ramp

These were large dirt ramps that the Babylonian soldiers built so that they could get onto the walls of Jerusalem.

siege towers

These were wooden towers that the Babylonian soldiers built around Jerusalem to enable them to shoot arrows over the walls of Jerusalem.