Sensing her target through the magics being wielded, Daiya draws on her dragonmark, twisting space to appear directly behind the spellcaster.

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Dimension Leap, sword out, to target. Draw Sword. If Dimension Leap is swift (I don't have my books handy), I'll also make an attack, releasing the stored spell if that succeeds. I'm trying to flank with Shard, who can hopefully also reach Dura, so align my teleport appropriately. If I can't attack and she does anything to provoke, I'll take the attack of opportunity. Use the rolls below if you like.

(1d20+11)[21]
(2d4)[4]Miss on 2
(1d10+5)[11]Damage
(3d8+6)[21] Spell damage