Urza, Lord High Artificer | Worldwalker Helm | Echo Storm

Cards

Cast
Echo Storm by paying ({3} magic symbol) ({U} magic symbol) ({U} magic symbol) .
Echo Storm triggers, copying it for each time you've cast your commander from the command zone this game.
Resolve all
Echo Storms, creating a token copy of
Worldwalker Helm and a Map token for each
Echo Storm.
Activate
Urza's first ability by tapping a Worldwaker Helm and a Map, adding ({U} magic symbol) ({U} magic symbol) .
Activate a
Worldwalker Helm by paying ({1} magic symbol) ({U} magic symbol) and tapping it, creating a token copy of the
Worldwalker Helm token and a number of Map tokens equal to one plus the number of
Worldwalker Helms you control as you resolve this ability.
Activate
Urza's first ability twice by tapping two Maps, adding ({U} magic symbol) ({U} magic symbol) .
Repeat from step 5.