I spent a bit of time jiggling batfactors.
Here's what I have:
skill 7131 Kodiak Moment 0 0 regular, once, bear !! instant crit
skill 7132 Grizzly Scene 0.5*monsterhp 0 once, bear
skill 7133 Bear-Backrub 0 -20 once, stun 1, bear
skill 7134 Bearly-Legal 0 0 once, bear
skill 7135 Bear Hug...