When it comes to Zerg Ultralisk tactics there are a number of different situations you may find yourself in, where Ultralisk units will excel, and a number of situations where they can be easily destro[censored] . It is important to play towards any unit's strengths in order to achieve success. These units are the strongest heavy ground unit of the Zerg and have been around since earlier installments of the game.
With the introduction of the "Burrow Charge ability", the Ultralisk unit will be able to burrow and then charge a few feet in front of them in a quick movement. This ability will allow them to approach their enemies more efficiently, as currently they are easily countered and often times, not worth their high mineral and gas price to spawn. Also, they are large units that often get stuck behind other units and behind structures as well, thus this new ability will allow them to move around the map more efficiently.
The Ultralisk comes with one armor and has its own Chitinous Plating upgrade that increases its armor by two. The Ultralisk is immune to snare, stun and mind control effects such as the Neural Parasite or Fungal Growth. This unit is also classified as massive which allows it to trample through Protoss forcefields.
These units can do splash damage and are great at taking on swarms of lesser units like Marines or Zerglings. However, these units are rather vulnerable to Siege Tanks who are capable of taking advantage of terrain or the placement of structures, to attack these units without any chance of retaliation.
Ultralisks are best used as a front line troop, they are an unit that have a large amount of hit-points and defense, and are great at taking the bulk of a forces damage. At the front of a large group they can absorb enemy fire, allowing weaker units to get into the fray. Being as large as they are, these units can be intimidating and therefore and are typically targeted first, this plays to their advantage.
Hiding a large group of Zergling units, mixed in with Baneling units, behind a wall of Ultralisks is a great way of getting Banelings to the thick of things where they can be devastating against enemy units and structures.
A drawback of the Ultralisk, however, is that this unit is unable to attack air units and is therefore confined to fight only on the ground. Despite their large size, they are unable to reach enemy air units and this can be an annoyance. Make sure you have a number of air support units if you spawn these guys because some air units can be a real pain in any Zerg player's side. These units are rather quick though and are capable of getting away from most air units, as they can quickly move where they need to go and can take much of what these opposing units can dish out, due to their high health and defense.
These units are also very good at walling in areas. Walling in is when you use units or structures as walls by placing them side by side. These large units can plug up small areas like ramps or alleyways, making it difficult for enemy units to p[censored] without first snuffing them out. These units can therefore be used to create portable walls, which is a situational strategy for any Zerg player to follow, as the Zerg require mobility to be supremely effective in battle. For the Zerg, strength lies within their ability to field large numbers of units simultaneously. Individually Zerg units are rather weak, but as a swarm they become very effective in close-quarter combat.
The Ultralisk is also an a great unit for destroying highly armored opponents and are the bane of marine units as well. These large critters can really ruin a Terran player's day and when the "Burrow Charge ability", is included into the game, these units will become a force on the battle field. This ability is a much needed improvement, however, as this unit is, at times, too large for it's own good.
