1.e4e62.d4d53.Nc3Nf64.Bg5...This leads to the so-called normal variation. White defends the pawn indirectly by pinning the knight on f6 and creating the threat of e5. Now Black has several possibilities at their disposal.4....dxe4Taking the pawn is what I personally consider the best - it leads to the so-called Burn variation.4...Be7This natural move, defending the pin, is also quite possible. Here White has several options, but the most common is to go5.e5Nfd76.h4Leading to the so-called Alekhine-Chatard Attack.4...Bb4Even this pinning move is possible, leading to the very sharp McCutcheon variation.5.e5h6And it turns out Black doesn't lose a piece here!4...h6To be fair, Black can even consider playing this move, involving a pawn sacrifice and claiming they will get a lot of compensation for it.5.Bxf6Qxf66.exd5Bb4And here Black has some compensation due to the bishop pair - and play is very forced. This line seems more suitable/likely to appear on the master level and beyond.