Setting Raigeki on Heishin and Nitemare

Setting Raigeki is a useful play in many situations during FM speedruns. This video shows why it is generally preferred to set Raigeki when facing a monster you can't beat: [Video coming soon]

Below is in-depth analysis of setting Raigeki on the second turn on Heishin and Nitemare.

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HEISHIN
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Raigeki is notoriously ineffective against Heishin when used on turn 3 to clear two strong monsters. This is because he has about a 50% chance of Megamorphing a monster from his hand on the next turn. If he doesn't Megamorph, he usually sets a trap, which you can't clear immediately without risking Megamorph again.

One way around this is to set Raigeki on turn 2 when facing a monster that THTD can't beat. This causes Heishin to use Harpie's Feather Duster about 45% of the time, which is bad but not unrecoverable, as you should have outs to GG/MBD besides Raigeki. When he doesn't use HFD, the duel often goes like this:

Turn 1: You toss 5, Heishin plays GG
Turn 2: You set Raigeki, Heishin plays MBD
Turn 3: You play THTD, activate Raigeki and attack

Now on his turn 3, Heishin is forced to play a monster without equipping it since you have board control. Since you've destroyed his two strongest monsters, that monster is usually beatable with a 3300 THTD, and sometimes beatable with a regular THTD. If this monster doesn't destroy your THTD, you've basically won the duel. If it does, you still have one more turn to draw what you need.

This strategy works even better when Heishin starts B. Skull/BEWD/Metalzoa. Heishin will often drop below 3000 on his third monster, and it's not so bad to lose Raigeki to HFD when you only need 1 equip to win.

Furthermore, if you draw Widespread Ruin on turn 3, you can set it before activating Raigeki, destroying a total of three monsters. Better yet, you can get a cheap win if he sets a magic. Drawing Widespread is generally useless if you hold Raigeki and then use it.

In addition to the above benefits, setting Raigeki allows you to draw 1 extra card since you're able to toss 5 cards instead of 4. This card could be the equip or monster you need to take control of the duel.

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NITEMARE
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While Nitemare can't Megamorph, he presents a few common situations that punish players who use Raigeki on turn 3 rather than setting it turn 2. The main one is fusing for MBD. Imagine a situation where Nitemare has the MBD fusion in his hand and his three best monsters are PUGM, B. Skull and THTD. If you choose to hold Raigeki, the duel goes like this:

Turn 1: You toss 5, Nitemare plays PUGM
Turn 2: You toss 4, Nitemare plays B. Skull
Turn 3: You use Raigeki, Nitemare fuses for MBD
Turn 4: You can't draw a 3800 and lose

If you choose to set Raigeki, the duel goes like this:

Turn 1: You toss 5, Nitemare plays PUGM
Turn 2: You set Raigeki, Nitemare plays B. Skull
Turn 3: You play THTD, activate Raigeki and attack; Nitemare plays THTD in Defense
Turn 4: You play another THTD and take control

Note that even if Nitemare didn't have the MBD fusion, the second duel would be superior because you would be able to destroy his THTD and take control on turn 4. In the first duel, Nitemare's THTD would be in Attack position on turn 3, so you would have to wait a turn to destroy it. This would give Nitemare one more turn to topdeck something bad.

Just as on Heishin, setting Raigeki allows you to destroy an additional monster when you draw Widespread, and it gives you additional draw power.

Note that Raigeki should not be set on turn 2 against a BEUD, since Nitemare can kill you in one turn if his next monster is BEUD/GG/MBD/PUGM. For the same reason, setting Raigeki on turn 1 against Nitemare is risky and generally inferior to turn 2 despite giving you more draws.