"And that's how we do it on planet Earth you overgrown space cockroach."
~ Sam taunts Ugh-Zan IV
Ugh-Zan IV is a very large creature, which moves quite fast due to his vast size. He will stomp on the player at every opportunity. He's generally not considered as difficult as Ugh-Zan III. He has very high health regeneration that increases the lower he is on health, and while regenerating, cannot be killed with any of Sam's weapons. He'll stomp you if given the opportunity, and fires wide, fast-moving projectiles that, while easily dodged, do considerable damage.
Ugh-Zan IV is constantly surrounded by Mental's forces (Khnums, Major bio-mechanoids and Technopolips) and will spawn in reinforcements until either he or Sam is dead. He, along with his infinite horde of alien backup, is Mental's last defense against Sam and the Time-Lock - or so Sam thinks.
"This is the fourth incarnation of the vicious Ugh-Zan, last of the Warlock giants. It is alleged to be the biological father to Ugh-Zan III - a paradox attributed to an accident with an experimental time-machine. Biologically grown bio-mechanical quadruped serves as a base replacing the legs, which Ugh-Zan IV lost in the great battle for Alpha Centaury. He has two natural arms (cybernetically augmented), and two completely artificial ones. There seems to be a particular affection to having four arms in the Ugh-Zan dynasty. While his skin is very thick in general, there are allegedly several soft spots on his back. It is hard to get there, though, because he can spin quickly on his base."
- As soon as the battle starts, the player needs to go left into the building nearest the large structure in the center of the arena. This building has a Jetpack, which is required to kill Ugh-Zan IV (this means that it is impossible to beat the boss if you have Powerups turned off to increase your score, because that stops the Jetpack from spawning). Be sure to grab the Health and Armor pickups in this building, you will likely need them.
- Avoid hanging around on the ground for too long. Ugh-Zan's stomp attack is devastating in terms of damage, while the hordes that arrive to assist him can kill you quickly if you aren't careful and evasive; most of the spawned enemies as well as Ugh-Zan himself fire fast-moving projectiles at you, which can lead to a near unavoidable wall of incoming damage.
- Once the Jetpack is obtained, the player needs to fly up and start looking for a large green/red pile. When this pile is found, fly down and it'll turn into a gigantic pile of scaffolding poles. Walk over one of these piles to pick a pole up.
- Now, fly around and dodge Ugh-Zan's attacks until he starts wrestling a Sandwhale. While he is fighting the Sandwhale, fly to Ugh-Zan IV's back and get close enough so that a red outline of a pole appears on his back. When this red outline is seen, throw the pole to stick it into Ugh-Zan's backside.
- Eventually after fighting off the Sandwhale, Ugh-Zan will be struck by lighting. This does some damage (depending on the number of poles in his back) and temporary shuts off his regenerating ability.
- The goal is to toss five poles into Ugh-Zan's back. When five poles have been shoved into his back, he will have almost all of his health taken away by a lightning strike, along with his regenerating ability temporary being shut down. A few charged SBC Cannon shots will finish him off.
- Three or so poles can work if the player has already softened up Ugh-Zan IV with several charged Cannon shots, or if he gets struck by lightening twice in rapid succession, dropping his health to next to nothing.
- The enemies that spawn with Ugh-Zan are not a threat and do not give points when killed. It is typically easy to dodge their projectiles while flying around with the Jetpack. However, use care if you have to land while your Jetpack cools off.
- If the player needs Cannonballs to hurt Ugh-Zan IV, there are many scattered throughout the level in the buildings. Be careful if you use the Cannon against foes on the ground, a charged shot will bounce and likely miss its intended targets if proper timing and sufficient aim is not applied.
- The Devastator or Rocket Launcher will also work if you run out of Cannonballs, but obviously will require more hits to inflict comparable damage, so five poles will likely be required. Note though, that Cannonball pickups will respawn in certain places, if you get the time to look for them. Devastator Shells are however in limited supply while an infinite Rockets crate is present.
- In Tourist mode, you can beat the boss with only 1 pole, and you don't need to wait for the lightning to strike.
|Name and Icon||Description||Notes|
|The doorman should wear a suit||Awaken the Guardian of Time. (Start the fight with him.)||-|
|Serious Sam||Complete the single player campaign.||Doesn't need to be in one session.|
- The rockets fired by Ugh-Zan IV use the same model as the Major Biomechanoids' from Serious Sam HD.
- Ugh-Zan IV being the biological father of Ugh-Zan III due to a time-travelling accident bears similarity to the lineage of the character Zaphod Beeblebrox, from Douglas Adams' The Hitchhiker's Guide to the Galaxy. Zaphod's father was Zaphod Beeblebrox II, his grandfather Zaphod Beeblebrox III, etc., also due to a time-travelling accident.