Command & Conquer: Red Alert 3/Empire of the Rising Sun units

Burst Drone
Another nice Empire advantage aerial observer unit that can snuff out those nasty spies. Also they can attach themselves to vehicles and slow them down which is helpful. If you want, you can hit the suicide button on them (to make both this unit and the vehicle they are attached to blow up), but don't do it if it's not on a vehicle because you only get one shot. They're nice and cheap so you can mass produce them no problem and they're great for scouting.

Engineer
Engineers are the same for all factions, besides their secondary ability which with the Empire allows them to run fast for 10 seconds followed by brief exhaustion for 5 seconds.

Imperial Warrior

 * Imperial Warrior: Standard imperial infantry with a great secondary ability which allows them to charge infantry with katanas for 10 seconds and hack them to pieces. One hit infantry kills. To Clear a garrisoned building order your warrior to do a banzai charge and then order the warrior to enter the structure.

Tankbuster
Long range anti-tank/vehicle unit. Unlike other factions, they cannot attack air although their range and damage is consistent and awesome, especially as they gain ranks. Secondary ability lets them burrow into the ground to avoid crushing and ambush the enemy.

Shinobi
A variation of an Allied spy which allows you to infiltrate enemy structures to perform a variety of structural damage. They also have a smoke screen secondary ability and unlike spies, they can attack and kill infantry in one hit kills but can’t take the form of enemy units.

Rocket angel
The equivalent of the Red Alert 2 Rocketeer that had belonged to the Allies. This alternate reality has allowed the Empire of the Rising Sun to develop the technology first with much improvement. This is a truly devastating unit against air and ground units. The secondary ability stops an enemy unit in their tracks.
 * Counters: Rocket Angels were tough Foes even if MiGs or Apollos can counter them.

Yuriko Omega
Depending on how you look at it, she is truly the best "super unit." Every faction gets one, the Reds have Natasha (no longer Boris), the Allies have Tanya and the Empire has Yuriko (a pun off of Yuri, the main villain from Red Alert 2 who had supreme mental powers). She is highly powerful and can crush any ground unit with much ease. She does not have a one hit kill, but she picks enemies up with her mind and will crush them. It takes a few seconds, but you can juggle multiple units into the air and if you're good with the timing you can keep 3 or 4 tanks and troops in the air helpless while you quickly destroy them. Her secondary ability is amazing; she projects huge lines of psychokinesis to destroy any enemy infantry. Truly devastating. If you lose her, the AI will not warn her about her death, but despite this she can win on most one on one fights.

Mecha Tengu
The combination of the Empire's Tengu offers you a lot of versatility. The secondary ability allows this ground based anti-infantry unit to turn into a jet for anti-air capabilities.

Jet Tengu
The jet form of the Mecha Tengu, which is fantastic for anti-air and giving the Empire Imo a hard time. They are great to build in masses, as they have no airport or need to refuel like the Allied jets, which will win in about a 2-3 to 1 ratio (because of the limit of attacks and need to refuel they are much more powerful). The transformation back and forth takes a little bit to recharge, but not much in the long run.

Sudden Transport
Allied spy in a transport. As long as there are no locators around like bears/dogs/burst drones, it easily tricks the computer AI. Not as effective against human players.

Tsunami Tank
Standard Empire tank. It is amphibious with fairly quick movement to dodge Dreadnought/V3 missiles, but Battleships and Subs will tear them apart. It is more of a supplement to naval units but it's great to have the versatility just like with the Tengu/VX units.

King Oni
This is the unit you see in the cinematic ripping cities apart like a giant Voltron shooting beams out of his chest. This is a great unit for its sheer destructive power. It's a little pricey, but definitely worth it for ground assaults as long as you make sure to protect him with anti-air. He can crush units and his secondary ability is to run full force to wherever you click and pretty much anything in between from infantry to tanks will be crushed and stomped into oblivion.
 * Counters: King Onis are tough foes even for Soviet Apocalypse Tanks much due to bull rushes were very devastating against even the toughest Tanks. The Best way to defeat them is using Aircraft or Tanya.

Striker VX
The Striker is the compliment to the Tengu, being the helicopter counterpart. On the ground it has great anti-air missiles similar to IFV missiles. In the air it is great in numbers and to help supplement your navy if necessary. This unit combined with the Tengu is a great combo.

Chopper-VX
The air form of the Striker-VX. It turns into a basic helicopter with ground attack.

Wave force Artillery
Fantastic long range vehicle akin to the V4/Athena. It hits hard and can take out defenses quickly to let your King Onis and infantry and Tengus assault. Their special ability reduces rate of fire.

Ore Collector
Collects ore. It has a secondary ability to pop out some anti-infantry cannons, so it can provide quick defense when those players rush your collectors as they are quite pricey and can cause your economy to stall easily.

MCV
Converts into a Construction Yard.

Shogun executioner

 * Shogun Executioner: A powerful Tri Bodied Walker that can absorb Tesla attacks and can walk on water and land. It does require air support but it will crush the soviets biggest tank and cut down most enemies in one hit. This unit is not buildable and is only available in certain missions of the Empire campaign.

Yari
A very cheap naval scout and pretty descent little attack sub, at only 800 gold. Great for starting out, but after a few tiers you'll just want to keep 1 or 2 around and focus more on the higher end Naginata. This unit also has a suicide button which is nice for taking out those nasty long distance battleships from every faction as they have a hard time attacking close.

Sea Wing
Another great accent to a Tengu/VX force. It can be great assistance to your navy by providing the only real naval anti-air support. It's a good idea to make 2 groups of these guys; 1 for your navy and 1 for air force. They can only go into anti-air mode over the water, but they can take down most dangerous units like Kirovs in 5/6's per navy.

Naginata
Every faction has a similar, more expensive destructive sub/ship that’s meant for protection of your large long range battleships. They are crucial on any map with a lot of water. These protecting a few Shoguns, can tear through an enemy's base defense very quickly, allowing your ground forces to tear them apart. Their secondary ability, which shoots out a volley of torpedoes that split apart, are quite deviating and will kill most early ships and heavily damage a lot of units in a fan-like spread. Exercise caution though, because they can hit friendly units.

Shogun Battleship
The battleship to end all battleships. Its attack has long range and is a straight shot by six cannons that can’t be stopped, unlike the other factions' attacks. It also has a great secondary ability that allows you to target an enemy vessel and ram into it, destroying any enemy vessel. Interestingly enough, you can even run over enemy commandos, which is really helpful when they are trying to plant a bomb to your ship. Truly the ruler of the seas.