Sämisch: 5.f3 with the ...c5 gambit is variation 3 of 6 in the King's Indian Defence course, a advanced opening course for Black (ECO E81). It runs 24 moves and begins 1. d4 Nf6 2. c4 g6 3. Nc3 Bg7 4. e4 d6 …. White plays f3 and Be3 to support e4 and maybe launch g4-h4. Black hits back at once with ...c5 and ...Nc6; after d5 the knight jumps to e5 and Black opens the e-file with ...e6. In the lesson every move is explained on a board and then drilled; it is free.
Move by move
1. d4 – White occupies the centre.
1... Nf6 – Develops and controls e4.
2. c4 – Gains space on the queenside.
2... g6 – Prepares ...Bg7.
3. Nc3 – Develops and supports e4.
3... Bg7 – Fianchettoes the bishop.
4. e4 – Builds the centre.
4... d6 – Keeps the knight safe and prepares ...e5 or ...c5.
5. f3 – The Sämisch: rock-solid support for e4 and a possible g4-h4 attack; it stops ...Ng4 tricks.
5... O-O – Castles first; the king is safe enough even if White pushes g4 later.
6. Be3 – Develops and prepares Qd2 and perhaps Bh6 to trade Black's best bishop.
6... c5 – Strikes at d4 before White is fully developed; it is a sound pawn sacrifice if White takes.
7. Nge2 – Develops and defends d4 and c3; White declines to grab the pawn.
7... Nc6 – Adds a third attacker to d4, so White must decide on d5.
8. d5 – Gains space and kicks the knight.
8... Ne5 – The knight lands on a fine central square, hitting c4 and f3.
The lesson goes on for 8 more moves, each with its explanation.
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