You should be focusing the Kabalite truebon venoms with 3-4 blastes and the ravagers/flyers. The blasterborn will be your biggest threat if you are running mech, with the ravagers close behind. Also, if he is running wyches DO NOT DEPLOY ON THE LINE (Assuming standard 24" separation.) If he can alpha strike your parkng lot you will be in for trouble. The next tactic you will have to watch out for is the venom block. If he runs lots of transports he can virtually stop your forward movement and force you to deal with the venoms instead of his anti tank. If he goes before you do not single block all of your tanks. Try to make two or three blocks that are separated but not isolated so he can't stop your movement forward. This last thing to watch out for are beast masters. They don't seem that good at glance, but 30 S3 rending attacks on AV10 on chimaeras really ruins your day and they are very durable.
Target Priority:
Blasterborn transports-> Ravagers/flyers->Beast Masters/wyche transports->Warrior venoms
Also on to your strategy do not scout with the vendettas.
DE will always have a cover save if played correctly, and anything that gets close will be shot by about 12 lances from the 3 blasterborn squads.
Hope this helps

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