I can synthetize your post with

phase1 normal damage
phase2 summon adds
phase3 water attack

It's similar to NM's crab if not for phase2.
it seems fun because it is well written but in game terms, I'll spam dps for the combat, exactly as I normally do.
Why? because I don't have tools (skills) for a different tactic. I can move outside an aoe attack (example NM gnat prince of pestilence) or move behind (old6arms), but I cannot interrupt a skill, CC an add, dispel a buff...