Ya, sidedash attacks leaves u open for too long it gets u killed. Generally speaking, if u sidedash, their forward dash attack will hit u 90%. As Marginal put it, thats forward/ diagonal forward is the way to get decent dmg only when u are punishing. Tho being too committed at this will get u punished by their forward dash/ airdash attacks. You have to know when they are committed in their dash attack or landing from a jump before your shot can make it. Other times as Temjin, make good use of your Left turbo bomb to harrass. It homes and bounces near them, takes a chunk of Varmour off and does a tiny bit of dmg. Other times when your are not committed to a dash, just keep firing RW while sliding and running (not dashing). Dont forget Temjin's special move, Surfing Ram (jump> fwdash> CW) which deals tons of damage on hit and homing is very good. Best used as a trump card against those who have lost sight of you and when time is running out as it depletes all gauges.