Why not just let the Rock Soldiers invade earth at any time?

[neatoman]

In season 1, Krang's ultimate plan is to open up the portal so his army can come to earth and "crush it". Considering that the portal pretty much always worked, why not send the troops in at any time? There really isn't much of a reason to pull a new scheme every week if you have an army at your disposal.

[IndigoErth]

I was going to suggest not having enough power for the Technodrom to do it, but I guess that was other seasons in which a new power source was always part of the latest plan. I dunno, good question. I guess that would have made it too easy.

[Icebot]

I think Krang wanted to do that most of the time except the end of season 1 / most of season 2, as the technodrome got pulled into Dimension X, Krang was satisfied it meant he gets to conquer Dimension X, Shredder was the one who was upset and wanted to conquer eaaarrrrth!

The end of season 2 is when Krang said the invasion can’t wait any longer so I think that’s when he got interested again and the technodrome was low on power for most of season 3.

At least in Shredder Triumphant, he did bring his rock soldier army to invade earth.

[Original TMNT Cartoon Fan]

I was going to suggest not having enough power for the Technodrom to do it, but I guess that was other seasons in which a new power source was always part of the latest plan. I dunno, good question. I guess that would have made it too easy.

Rock Soldiers hang out at rock soldier bases throughout Dimension X (mentioned in "Plan 6 from Outer Space"), so I guess it depends on if they are full-powered not.

We never see anything referred to as a "rock soldier base", except if the space station the Technodrome collides with at the end of the The Big Blow Out is a rock soldier base.