Stormrise

There's a really easy to get both Stormrise achievements Spray and Pray and Unleashed. It takes less than a minute for both.
Set up a skirmish and make sure you pick a map that you can use any unit. Many maps don't let you use all units.
I set up the energy to high just in case and make SURE you set up yourself to be the Sai.
You have to scroll up to your GT and hit X to switch factions. Hit it until the icon is a triangle pointing up.
Then start the match.
I made a matriarch first, and as soon as she was built I selected her, held down LT and moved the right stick to highlight the Acid Rain ability and it pops right away.
Then I made a Rage, and selected it as soon as it was built and held down LT and moved the right stick to highlight the rage smash ability and then that pops right away.
Watch the video if you need to. It's simple

Unleashed

"Select the character after being build and press Alt button and click on the Smash Ablity - Achievement Unlocked" This is not a computer, to use the ability hold LT and use your right analog stick and move it over the Smash abilitiy on top, achievement unlocked.

The only character that can use this ability is RAGE, which you can make on Mission 5. Right in the beginning you can unlock it.

The Fastest way to get this is by playing an Online match. It is dead so you will need a boosting partner to get this done!!!
You can also go into a skirmish match and get this.

Choose the Sai side and create a Rage Character

Select the character after being build and press Alt button and click on the Smash Ablity - Achievement Unlocked

To unlock this achievement you must use the special ability of the unit Rage, one of the Sai units. An easy way to do this is to start a multiplayer match as the Sai faction and recruit Rage and then use his ability anywhere.