Concept here is to use DPS summoners as a sort of fireball tower stand in. Oil traps will make the fire-based DPS pets do double damage, traps at each spawn, then a central build of mortars to blast away everything as well. If it cooks fast enough, this could be a decent Tier 2 option.
1 Summoner with Huntress/monk pets, 3 DPS summoners with Fire-based DPS pets at each hint 5, but within range of the empowering shrine. Perhaps 1 CDrag and 1 Cat each??