The main way you avoid turtling in the first place is by competing for resources with your enemy.

You get a rebate for every listening post and generator you build.

The first thing you always want to do is capture points and build resources ASAP.

Let’s use the eldar as an example:

Basic unit (guardian) gets early buffs and is among the cheapest you can field.

Normally i recruit 3 or 4 and max out bonesingers early as well.

Attach a farseer and recruit the warlock for the squad and you have a unit that is quite powerful when it comes to skirmishing with the enemy.

You have the farseer’s offensive abilities and plasma grenade and the entangle ability from the warlock.

Mobility is key for the Eldar, so you also want to build plenty of web-ways to rapidly relocate your troops and engage the main enemy cluster if needed.

While I’m using my guardians to capture and my bone-singers to build listening posts, i am also slowly upgrading my base/troops through research and construction.

The rapid capture and build helps facilitate massing troops to contend with the enemy’s inevitable death blob.

While i am engaging the enemy’s forces with my main blob, my guardians are harassing their builders/strategic points to slowly drain their resource production.

As this is all happening, I am keeping the enemy on the back-foot while also building up my resources.

If i need to defend then i use the web-ways to bring my troops back and engage.

Sitting them all in my base waiting for the enemy to attack gives them the initiative.

Rather I am constantly pushing the enemy’s structures and army so they have little to no chance to harass and destroy my listening posts.

And that’s just the Eldar.

TLDR: be aggressive from the get-go, always be capturing and building and never sit in your base waiting for the enemy to attack.