Its got evasive 3, throw axe and block 2 while being 20 nora less than Dirge. This is the rant about everything that other factions have better than you thread.
We do have mud elemental now...absorb, elemental fortitude, res. phys., mimic defense, 11 more hp, and a lot of movement-based cc, so SP has it's own overefficient runes. Sentry probably should't have both block/evasive 3 for 60 nora, though, since champs shouldn't be protected from everything (Fist of Bastion...I'm looking at you).