+2:All creatures you control have +1/+0 until end of turn.
0:Target creature you control fights another target creature then put two 1/1 red white soldier tokens to the battle field under your control.
-3:All creatures you contol have +0/+5 until your next upkeep. Put two 1/1 red white soldier tokens to the battle field under your control.
-12:All creatures you contol have +1/+1 for each creature and your opponent controls and has double strike and lifelink until your next upkeep.
These abilities look rather wordy. Could they be simplified a bit? The -3 also seems way overcosted for basically a Raise the Alarm plus half of Tower Defense.
You know, I really liked the additional creatures that kept spawning incedentally when activating this walker's abilities. Alex isn't wrong, though, this walker is wordy. Jace, the Mind Sculptor is a cool card (power level issues aside), but to get all 4 abilities on the card, it needs to do 4 simple things.
My suggestion would be to cut down to three abilities, and, to simplify the text, add:
"Whenever you activate one of Kariel, Strife Angel's abilities, put a 1/1 red and white Soldier creature token onto the battlefield."
The toughest part about designing planeswalkers is establishing a memorable identity. Having a trigger off of your activations seems like a good way to make players remember this card.