Super Robot Wars/Compact 2/Secrets

Obtained in this game

Vierres (Galaria Nyamhee)

Stage 2-4: Do not shoot down Galaria. Will join after the stage.

Gaplant (Rosamia Badam)

Stage 2-5: Convince Rosamia with Kamille. Will join immediately.

Vierres (Todd Guiness)

Stage 3-2: Convince Todd with Show. He will join in stage 3-5.

Kampfer

Stage 3-4: Play as the 3rd or 4th stage, deploy Shiro. If you play stage 3-3 before 3-4, Shiro will be unavailable for Stage 3-4.

Minerva X

Stage 1-6: Send Tetsuya & Jun to Space.
Stage 4A-3 (Earth Route): Kouji convinces Minerva X. Anyone can shoot it down after that. Will be available after Scene 4.

Mass Production Great Mazinger

Stage 1-4: Play after Stage 1-5.
Stage 1-6: Send Kouji & Sayaka to Space.
Stage 4A-2 (Earth Route): Play stage 4A-2 before stage 4A-3.
Stage 4A-3 (Earth Route): Tetsuya convinces and then shoots down MP Great Mazinger.

Full Armor Gundam

Stage 4A-4 (Earth Route): If by turn 10 enemy phase Mega Borg Benmel is still alive, Char Custom Zaku and RX-78 Gundam will be deployed. Defeat at least 1 of them with Bernie. You will receive it before the start of stage 5-5.

Billbine

Stage 3-2: Take the Byston Well Route in Scene 4 by clearing Stage 3-2 as third or fourth.
Stage 4B-2 (Byston Well Route): You get it in this stage if you cleared stage 4B-1 before this stage.
Stage 4B-4 (Byston Well Route): Otherwise you get it in this stage.
If you don't take the Byston Well Route, Billbine will be acquired normally in Part 3.

Wryneck

Stage 4B-4 (Byston Well Route): If you recruited Todd, you will get this unit at the end of this stage.

Apsalus (Aina Sahalin)

Stage 4-5: Reduce Apsalus to less than 20% HP, convince Aina with Shiro. Will join immediately.

Gouf Custom (Norris Packard)

Stage 4-5: Convince Norris with Aina and Bernie. Will join immediately.

Texas Mack (Jack King, Mary King)

Stage 5-1: Play as the 3rd or 4th stage.

Psyco Gundam

Stage 6-3: Play after stage 6-2. Have Kamille defeat the Psyco Gundam. Received before stage 6-5.

Obtained in a future game

Aggressive Beast (Dancouga)

Part 1: Upgrade all of Dancouga's stats and weapons at least once (Dancouga leaves permanently before the start of stage 1-6).
Part 2: Dancouga will get this attack before stage 4-6.

Extra V-Up Unit

Part 1: In Stage 1-6 defeat Bandock (Butcher). He leaves when HP < 30% or at the start of turn 5.
Part 2: Received after clearing stage 2-3.

Elpeo Puru

Part 1: In Stage 3-4, convince Reika, Beauty, and Toppo with Banjo, then shoot them down (using anyone). If Mega Borg Milene is still alive, she will deploy Puru. Defeat Puru.
Part 2: Obtained at the end of Scene 5.
Note that Puru and Puru Two are mutually-exclusive.

Sirbine and Silky Mau

Part 1: Take the Earth Route in Scene 4 (Clear Stage 3-2 as first or second).
Part 3: Receive at the end of Scene 4, along with Silky Mau.

Zwauth and Silky Mau

Part 1: Take the Byston Well Route in Scene 4 (Clear Stage 3-2 as third or fourth).
Part 3: Receive at the end of Scene 4, along with Silky Mau.

GP02A

Part 1: In Stage 3-3, have Shiro defeat Apsalus in Gundam Ez-8.
Part 3: In Stage 5-6, have Shiro defeat GP02A.

Neue Ziel (Anavel Gato)

Part 1: In Stage 6-2, allow Glemmy to retreat (by playing stage 6-2 after 6-3).
Part 2: In Stage 4-6, fight Gato with Kou, and then convince Gato with Quattro.
Part 3: In Stage 5-3, have Quattro and then Kou convince Gato.

Scene 7 (Compact 2-3)

Part 1, 2, 3: Clear Stage 6-4 of Part 3 with a final turn count of 777 or less.