Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.)
(Scroll to the end of it)
The evasion and haste along with prowess seems very strong for the deck.
UR delver's biggest weakness has always been its low threat density in a format tilted towards copious amounts of spot removal.
It also doesn't die to a single casting of lingering souls which is a big improvement given that every other creature in the deck does. attacking into 4 soul tokens with this could very easily end in a favor of the UR delver player; if they block 3:1 a single spell preserves your creature knocking out 2 tokens. 4:1 block and a bolt to a token also does the same.