Destroying the HRE from outside - how?

[Daelix]

1) Start as the Count/Countess of Najera.
2) Overthrow your king and take his kingdom.
3) Conquer all of Spain.
4) Conquer Jerusalem in a Crusade.
5) Conquer north Africa to connect Spain to Jerusalem, until your realm is marginally smaller than the Kaiser's.
6) Wait a generation to solidify your holdings/save dough for mercs.
7) Butter up el Popa.
8) Request Invasion.
9) Invade. Conquer every holding. Accept surrender.
10) Big Grey Blob is now Giant Soothing Yellow Blobs. Easiness.

 

[ChildeR]

IME the only thing that really works is trying to keep the HRE in a constant state of succession crisis. In that case the emperor will not always challenge the independence factions that happen, or might even be too busy to stop them. The claims go away after two successions (that you can help along), although some de jure territory may swear fealty to any random emperor. If megadukes/kings appear under the HRE, you also need to make sure they aren't jailed (e.g. kill them if that happens), or the emperor will be assured of a large force and rebellions are unsuccessful.

You can nibble also away at rebelling border territories if you are an adjacent duke or count. That doesn't require a large force if you time it right.

 

[CurtisManning]

With luck, the emperor will embrace an heresy, and all the european kings will attack him in holy wars. You can grab a piece or two yourself.