This achievement is fairly straightforward in that it requires you to special summon 50 times.
To do this, I used the deck "Ancient Warriors" (also a great deck to quickly get to platinum rank). Ancient Warriors is a deck that special summons approximately 5 times per-turn and usually wins quickly if you go 2nd. I used this video to get the achievement, although I made some minor modifications for budget reasons:
Additional tips: If your primary goal with Master Duel is to get the achievements, then I'd recommend the following tips:
- Invest your gems in decks that specifically aid to the completion of achievements
- Purchase the duel pass with 600 gems to obtain SR/UR crafting materials
- Do NOT surrender in a duel where you have made progress to an achievement. Stats are added up AFTER the duel has been completed, not during.
- Prioritise getting the achievements BEFORE reaching platinum rank. They become very difficult in higher ranks due to how the game is
- Focus crafting generic staples such as Ash Blossom, Maxx "C", and Pot of Extravagance early as they can be applied to any deck to improve their performance